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pulse vs hearth-rate | **Heart**-rate
Your pulse can have a little extra information on your health. A heart rate is the number of beats per minute that your heart makes, but on top of that a pulse can add the strength and consistency of the heartbeat at the point where it's measured. For example, a pulse can be characterized as "weak and thready" meaning your circulation system is having difficulty moving blood around due to a blood clot somewhere, even if your heart rate is normal.
As for sources for further reading, this is ELI5, not "quote your sources". Google it if you want more than a layman's explanation. | [
"The pulse is the rate at which the heart beats while pumping blood through the arteries, recorded as beats per minute (bpm). It may also be called \"heart rate\". The pulse is commonly taken at the wrist (radial artery). Alternative sites include the elbow (brachial artery), the neck (carotid artery), behind the k... |
how there can be so much money in network tv advertising and so little in comparative online advertising? | First off, Youtube is not struggling to profit; neither is Netflix. Netflix made more than $2 Billion in profit and $20 billion in revenue last year, far more than any TV station. Alphabet Inc (parent of Google/Youtube) is the 3rd largest company on earth with a value of $988200000000.
Secondly, there are few TV stations. There are only 5 broadcast networks in the US: ABC, NBC, CBS, Fox, and The CW. There are a few dozen pay channels available via cable. There are literally millions of websites. It's very easy to start a website. It's very difficult to start a TV station; you either need a license to broadcast or an agreement with a cable provider. So a TV station doesn't have to fight as hard for viewers.
Everyone sees the same ads on TV, whereas ads on websites are individualized. An ad that 50 million people see is worth more than an ad that 1 thousand people see. | [
"The advertising network market is a large and growing market, with Internet advertising revenues expected to grow from $135.42 bn in 2014 to $239.87 bn in 2019. Digital advertising revenues in the United States alone are set to reach $107.30 bn in 2018 which is an 18.7% increase from 2017 ad spend. This growth wil... |
Need to explain gravity and falling objects to my 9yo... | A simple thing that no one's mentioned is to put the piece of paper on top of and underneath the book when you drop them, rather than side by side. If they actually fall at different speeds, they would separate in one case. They'll fall together in both though, because the paper is shielded from air resistance effects by the book. If air resistance wasn't what was causing the difference, then this wouldn't matter. | [
"This particular equivalence often referred to as the \"Galilean equivalence principle\" or the \"weak equivalence principle\" has the most important consequence for freely falling objects. Suppose an object has inertial and gravitational masses \"m\" and \"M\", respectively. If the only force acting on the object ... |
in the way that people are able to build their own pcs, how far away are we from being able to build our own cellphones? | The major issue there is that most cellphone technology is extremely compact and build to fit around preselected parts where computers have components that can come in diffrent shapes and sizes, the designs are also far less modular. When I replied my iPhones charging port I had to use tweasers to re attach some components. They also lack a uniform standees design like computers making most parts incompatibl. | [
"The majority of people around the world still do not have access to personal computing. Many of the current efforts to bridge the digital divide are failing and it is difficult for organizations to make a dent in this large demand. The idea of providing a “laptop per child” sounds feasible in theory, but there is ... |
what is programmatic advertising? | Using programming (computers) to buy ads. Some are sold in what's called real time bidding. Basically when you visit a website with the ad in question whoever is selling the ad starts a short "auction" among some competitors and whoever has the highest bid gets the add and that's what you see. So obviously this all happens very fast, less than a second. The sellers then obviously will use computer programs to make this efficient.
When you visit a web page certain information is available about you from your browser, your IP (which can reveal information about where you are browsing from), cookies and other things that which can reveal more personal information. Computers are much faster than humans at calculations if you tell them the right thing to do so when all this information is available you can have the computer figure out how much to bid. | [
"While advertising refers to the advertising message, per se, advertising management refers to the process of planning and executing an advertising campaign or campaigns; that is, it is a series of planned decisions that begins with market research continues through to setting advertising budgets, developing advert... |
why do you hear so much more regarding desperate and lonely men rather than desperate and lonely women? shouldn't there be more or less an equal amount of both? | Women have far better support systems available compared to men.
It's socially acceptable for women to feel hurt and express those feelings. They usually get ample sympathy and support from friends, family, colleagues and the public. When a man tries the same, he's ignored, ridiculed and perceived as weak. | [
"Americans seem to report more loneliness than any other country, though this finding may simply be an effect of greater research volume. A 2006 study in the \"American Sociological Review\" found that Americans on average had only two close friends in which to confide, which was down from an average of three in 19... |
how is orange juice economically viable when it takes me juicing about 10 oranges to have enough for a single glass of orange juice? | They use machinery that grinds the orange down to more or less nothing, and can extract every tiniest little drop of juice from it. The machinery pretty much grinds up the oranges whole, skin and all, and then extracts every drop of juice from the ground-up mess. So they get more juice per orange than we can by hand, or even really with a countertop juicer. Multiply this by the scale at which they work - truckloads of oranges at a time - and that's how it works.
Did some IT consulting at the Tropicana factory in Bradenton, FL for a while. I learned some pretty interesting things about orange juice while I was there. Also had to wash my hair 2-3 times when I came home on Fridays or I'd smell like oranges all weekend. | [
"BULLET::::- Orange juice is obtained by squeezing the fruit on a special tool (a \"juicer\" or \"squeezer\") and collecting the juice in a tray underneath. This can be made at home or, on a much larger scale, industrially. Brazil is the largest producer of orange juice in the world, followed by the United States, ... |
Do we know of any contact between Ancient Egypt and East Asia ? | Ah. I enjoyed that book and it does an excellent job of telling stories, but yes, it's age shows in quite a few places. Short answer: no.
Essentially, the book is proposing a model called diffusionism, although hyper-diffusionism might be more accurate. This was a theory, or more accurately a methodology, that proposed singular origins for practically everything, thus, if something appears in two places, it necessarily moved from one to another. Independent development is generally rejected. Add to that, there is a longstanding tradition in European thought called *ex orientia lux* that tends to view everything a arising in the Eastern Mediterranean region, particularly Egypt, and spreading from there. These can lead to conclusions that can sometimes seem a bit absurd, such as the one you give--Austronesian ship design, from materials used to the rigging used, has practically no similarity with Egyptian design.
Today, diffusionism is rejected as a default explanation. It happens, certainly, but is to be demonstrated rather than assumed. | [
"Eastward contacts are represented by objects and motific works of ancient Egypt found in the Near East, including modern Anatolia and Byblos and those ancient regions around Canaan and Syria. Some kings of Byblos have been found buried with Egyptian items.\n",
"Foreign artifacts dating to the 5th millennium BCE ... |
why do some women look super pregnant at 8ish months, yet others are barely noticeable? | The boring, obvious answer is that women have a wide variety of body types and sizes. A tall, larger woman will appear less pregnant than a short, small woman. A woman with a tiny waist will show a pregnancy more than a woman with wide hips. | [
"BULLET::::- Women are more susceptible to develop diastasis recti when over the age of 35, high birth weight of child, multiple birth pregnancy, and multiple pregnancies. Additional causes can be attributed to excessive abdominal exercises after the first trimester of pregnancy.\n",
"Two months later, all women ... |
Is the next generation of humans getting stronger and taller than the previous one? Also when would it stop? | Humans are generally getting taller and stronger than previous generations. Many scientists believe this is due to nutrition (increased calories, increased protein intake) rather than genetics. Given that vitamins and proteins are ubiquitous, it is unlikely that height would increase as a function of nutrition. | [
"Improved nutrition is another possible explanation. Today's average adult from an industrialized nation is taller than a comparable adult of a century ago. That increase of stature, likely the result of general improvements of nutrition and health, has been at a rate of more than a centimeter per decade. Available... |
What is the place of the battleship Yamato in the Japanese consciousness/culture? | I would definitely say the Yamato has some sort of place in the hearts of the Japanese people even today. In the late 30s, when it was laid down it was praised for being the biggest battleship in history and at the time many people still thought that size was the most important feature for these kind of Battleships.
In theory it outgunned and outranged any US or British Battleship it would have faced, which in the thinking of WW1 or the Russo-Japanese War was the key to victory.
History taught us that it wasn't enough, although the Yamato also had design flaws, as [/u/kieslowskifan](_URL_0_) pointed out in this earlier [thread](_URL_1_).
While the Japanese were proponents of naval aviation themselves, they underestimated just how vulnerable giants like the Yamato would be to attacks from the air.
The whole concept of Battleships proved to be flawed in WW2, as can be seen in many other exemplary cases like the Bismarck, the Roma or the Sinking of the British ships 'Prince of Wales' and Repulse (by the Japanese themselves).
And although many famous ships were essentially a waste of resources there is often still an almost mythological meaning to them in their respective countries, just for what they represented at the time and how tragic their loss was. ('Bismarck' for Germany, 'Hood' for Britain, 'Arizona' for the USA ...) | [
"\"Yamato\", and especially the story of her sinking, has appeared often in Japanese popular culture, such as the anime \"Space Battleship Yamato\" and the 2005 film \"Yamato\". The appearances in popular culture usually portray the ship's last mission as a brave, selfless, but futile, symbolic effort by the partic... |
Going into the Korean war, did the US ever have the goal of completely absorbing the north into the south, or was an eventual retreat from the Yalu planned? | Going in was long before the Yalu. The intent was simply to keep the south from being incorporated into the north. Americans' concern was not to be embarrassed by having to retreat from Pusan. There was no UN mandate to do more which is why it was a UN police action, not a US war. Anyway, America was war weary after WW II and had disarmed. Civilians could buy jeeps and M-1s. Optics for Norden gun sights were available in the first simple catalogues of Edmund Scientific. The focus was on Europe and we certainly didn't want war with the new Communist regime in China. | [
"In the Korean War, the United States and the United Nations officially endorsed a policy of rollback—the destruction of the North Korean government—and sent UN forces across the 38th parallel to take over North Korea. The rollback strategy, however, caused the Chinese to intervene, and US forces were pushed back t... |
Is there literally ZERO resistance in superconductors or is it just miniscule or neglectable (like stuff normally is in real-life as opposed to theory)? | The best theory we have suggests that the electrical resistance of a superconductor can be exactly zero. Unfortunately it's a bit tricky to definitively validate this result experimentally since we simply can't measure a resistance of 0. Even though [most experiments seem to show that the resistance vanishes](_URL_1_), there is always an uncertainty associated with the instruments used that prevents us from saying that the resistance measured truly is zero.
Nevertheless, through ever more sensitive measurements, we can increasingly lower the upper bound of whatever finite resistance (if any) might exist. For example, for high purity aluminum, the [resistivity](_URL_0_) (or the specific resistance) has been measured to be less than 2.5\*10^(-25)Ωm. This number corresponds to a drop of at least 13 orders of magnitude at the superconducting transition, and is more than 17 orders of magnitude smaller than the resistivity of copper at room temperature (1.6\*10^(-8)Ωm). For all practical purposes we can say that the resistance of such superconductors really is zero.
edit: corrected units | [
"Superconductivity is the set of physical properties observed in certain materials, wherein electrical resistance no longer exists and from which magnetic flux fields are expelled. Any material exhibiting these properties is a superconductor. Unlike an ordinary metallic conductor, whose resistance decreases gradual... |
Just how long has vinegar been around in any form? | Vinegar is created by *acetobacter,* a kind of bacteria that is naturally occurring- notably, occurring in the guts of fruit flies. When yeast ( a fungi) encounter sugar, they will start to ferment it into alcohol. If *acetobacter* bacteria are present ( and, of course, that can occur because fruit flies are going to be drawn to the smell of fruit juice) and conditions are right, they will begin to ferment the alcohol to acetic acid.
Whenever wine, beer, hard cider etc are made, there is a chance that it will be turned into vinegar accidentally. But if , say, a farmer had vinegar in a barrel, adding wine or cider to it would result in more vinegar being produced.
So, essentially, your question is , how long have people done fermentation, made beer or wine? That's going back to [at least 7,000 BC , for China.](_URL_0_) | [
"Vinegar was known early in civilization as the natural result of exposure of beer and wine to air, because acetic acid-producing bacteria are present globally. The use of acetic acid in alchemy extends into the 3rd century BC, when the Greek philosopher Theophrastus described how vinegar acted on metals to produce... |
When was the second first developed as a unit of time? Were there any areas where a different standard was used? | hi! I've got a pile of links for you, so settle in...
First up, the FAQ has a couple of posts on [Hours, minutes, and seconds](_URL_11_)
Origins
* [Has everyone always used a 24 hour day?](_URL_5_)
* [As far as I can tell, nearly all of the world divides a day into 24 hours, each of which in turn divides into 60 minutes. When and how did this come about, and were there any radically different systems of time that we've now lost?](_URL_6_) - Sumeria, also China, Japan, Scandinavia
* [How did people decide on how many seconds there would be in a minute, how many minutes in an hour, and how many hours in a day?](_URL_9_) - Babylon
* [How/when did we develop measurements of time?](_URL_13_) - Babylon
* [When did the hour-minute-second system of measuring time (in particular, using base 60) become the world standard, and what other ways of measuring times of less than one day have been common?](_URL_1_) - Babylon
* [What is the history of time(keeping)?](_URL_3_) - Mesopotamia, also Mesoamerica
* [When was our concept of time developed? How did other cultures in the past measure time? When did the world agree to the 24 hour day?](_URL_7_) - also Inuit
* [How did an hour become an hour?](_URL_12_) - Europe
* [In a world that can't agree on anything else, how did we all come to use hours, minutes and seconds?](_URL_0_)
Other systems
* [What were the common ways of time measurement in ancient Egypt and Mesopatamia?](_URL_10_) - Egypt
* [Have we always used a 12 or 24 hour clock for measuring time? [x-post from /r/AskHistory]](_URL_2_) - Rome, China, Japan, Maya
* [Did Far East Asia use the same standard units of time measurement (seconds, hours, days) that we use today?](_URL_4_) - China
* [Did/Do native Americans have their own time system ?](_URL_8_) - Alaska
| [
"In 1832, Gauss proposed using the second as the base unit of time in his millimeter-milligram-second system of units. The British Association for the Advancement of Science (BAAS) in 1862 stated that \"All men of science are agreed to use the second of mean solar time as the unit of time.\" BAAS formally proposed ... |
When, how, and why did sports (in general) become such a high-dollar enterprise in the United States? | ( I'm typing this on my phone, so please excuse any grammar/spelling mistakes)
Although I'm not an expert, I would have to guess this happened around the late 1800s/early 1900s. During this time Americans disposable incomes and leisure time increased due to achievements by unions and other average Americans. Major league sports was a new way to pass the time. The earliest specific example of major-league organized sports would be (Vincent?) Spaulding, the baseball magnate after whom his baseball brand was named. He was the first to realize how much money could be made in organized sports, and his league included teams like the Black Sox.
Sports entertainment became really popular because it was a cheap alternative to things like going to the opera, museums etc.. So it appealed to many poor/working class people. It was a way to relax on the weekend after a long week of manual labor. To cater to this crowd, games were made to be a lot more rowdier and beer was sold at events. Later, to make baseball appear to more rich folks, the stuff I mentioned before was removed from games.
Also, speaking about other countries, I cant really think of any example of major organized sports before my previous example. I would guess that with increasing Americanization around the world, American culture seeped into foreign cultures, and sports was a part of it. | [
"Many factors combined to produce an explosive growth in this new sport which had been imported from the United States. The number of teams grew from 8 in 1985 to around 40 by the end of the 1980s. In addition, the teams from larger cities were able to professionalise further by obtaining large sponsors, attracted ... |
after showers, whenever i rub my skin i get rolls of dirt/dead skin cells. why is this? | You need to exfoliate better. Or shower more often. Grab a wash cloth or loofa and wash, don't just use your hands. | [
"In general, the skin becomes swollen, itchy and red. This is a result of compression of mast cells, which are hyperactive in these diseases. These mast cells release inflammatory granules which contain histamine. It is the histamine which is responsible for the response seen after rubbing the lesional skin.\n",
... |
why does 25 mph on a bicycle seem so much faster than in a car? | You feel like you're going extremely fast on a bike because you *feel* more.
Cars have very well developed suspension systems that "even out" the bumps on the road. As long as you're not dealing with a serious pothole or a speed-bump, the car's suspension is going to face-tank most of the shock so that you don't have to. Larger tires can also take some of the shock out of the road, but it's not as effective. Bikes generally *don't* have awesome suspension, and tires of *comparable* size. That means that you feel every bump in the road, or close enough to every bump in the road as not to matter.
Beyond that, cars are enclosed capsules. Your body's perception of "speed" relies on three things: what you see with your eyes, what your inner-ear feels, and what your skin feels. When you're on a bike, you can feel the wind running over your body. That allows you to "feel" your speed when you aren't accelerating or slowing down. Your eyes give you a sense of speed, but the brain is pretty good at filtering out unwanted implications from the eyes.
> Side Note
> The Inner Ear mostly just registers acceleration, for the purposes of this conversation. It picks up when you speed up, or when you slow down. It's also a part of your sense of balance, but that's not too crucial to note in this situation.
It's basically a combination of being able to feel the wind, and the poor shock-absorption. | [
"A standard lightweight, moderate-speed bicycle is one of the most energy-efficient forms of transport. Compared with walking, a cyclist riding at requires about half the food energy per unit distance: 27 kcal/km, per 100 km, or 43 kcal/mi. This converts to about . This means that a bicycle will use between 10-25 t... |
Zion Harvey got a double hand transplant at 9 years old. Will his hands continue to grow along with the rest of his anatomy as he ages? | Yes the cells will keep working normally and normal physiological growth is expected. Abnormal groiwth is also relatively common (please correct me) due to post transplant medication that supresses the immune system thus not stopping some spurs of organ/limb growth that medication would normally stop.
PS: I'm by all means not an expert. This was a fact I know due to a friend who has received a transplant, and honestly, I asked him the same question...
Which (specifically talking about hand transplant here) DNA is in the hands? With skin being able to regenerate, I'm not sure. The hosts or the donor DNA?
:) | [
"On July 28, 2015, doctors at the Children's Hospital of Philadelphia performed the first successful bilateral hand transplant on a child. At the age of 2, Zion Harvey lost his hands and feet to a life-threatening infection. Six years later, at age 8, he had both of his hands replaced in a double hand transplant.\n... |
where did trigonometric functions come from? and why do they work? | Trigonometric functions were developed by various ancient cultures, mostly dealing with measuring astronomic phenomenon which requires dealing with angles and triangles and such.
Basically, we had a certain set of questions (if you know the sides of a triangle how to calculate its angles, and vice versa) that trigonometric functions were developed to answer.
Different cultures tackled the problem differently. For example, Euclid and Archimedes used various geometric proofs to get the same answer.
Ultimately, mathematicians developed tables. They drew various triangles of various shapes, measured the sides and angles and wrote down what all the answers were.
The "table" method is what was basically used under modern day calculators came about. Before then, if you wanted to know the sine of an angle, you measured the angle, then looked the answer up in a table in a book. | [
"In mathematics, the trigonometric functions (also called circular functions, angle functions or goniometric functions) are real functions which relate an angle of a right-angled triangle to ratios of two side lengths. They are widely used in all sciences that are related to geometry, such as navigation, solid mech... |
what happened to telescoping fm antennas on cars? | Most new cars embed them inside the windshield or rear window which gives them a much better and bigger area of reception. The wire used is nearly invisible to the eye and you don't have to worry about a motor burning out or breaking it in the car wash as with the telescoping ones. | [
"The first 2,200 cars produced used a windshield-embedded antenna. This type of antenna proved to be unsuitable with poor radio reception. Oftentimes the radio would continually \"seek\", attempting to find a signal. A standard whip antenna, which was later changed to a manually retractable antenna, was added to th... |
if heat rises up, why does global warming occur instead of the heat just dissipating through outer space? | global warming is the buildup of gasses that PREVENT exactly what you are talking about (heat dissipating up, its called albido). These gasses act like a mirror pointed back at earth, reflecting said heat back into the system. | [
"Here on earth, the sun delivers lots of bounce, and the atmosphere surrounds it with a wall that reflects the energy back in. In outer space, however, there’s nothing — a vacuum — and the bounce all disappears very quickly, leaving very little moving. Lack of motion means little heat, and almost no transfer — very... |
Would we be able to detect an extraterrestrial spacecraft in orbit around our Sun? | [Voyager](_URL_2_) or [Voyager](_URL_0_)? :P
In all seriousness though, [this](_URL_1_) says that by 2028 we hope to have detected 90% of all near-Earth asteroids of diameter 140 meters or larger. So it's *very* unlikely we'd detect a Voyager-sized spacecraft in orbit around the Sun (unless it happened to be at the same orbital radius as Earth, and pretty close ahead/behind in our orbit). Orbiting around the *Earth* however, I'm not sure there's a single answer. The probability of detection would depend strongly on the orbital radius. | [
"Interstellar spacecraft may be detectable from hundreds to thousands of light-years away through various forms of radiation, such as the photons emitted by an antimatter rocket or cyclotron radiation from the interaction of a magnetic sail with the interstellar medium. Such a signal would be easily distinguishable... |
what is the catch with those auction sites that claim to sell ipads and high end laptops for $20? | You have to pay for each bid, and you can only improve the previous bid by a small increment each time. So as an example. Lets say an IPad costs $500. Each bid costs you $1. You can bid it up by .01 each time. So in aggregate people need to spend $2000 to win the right to buy the item for $20. And once people start bidding they feel like they have a certain amount invested so they keep going. Plus there are bots that autobid things up. | [
"Amazon introduced Amazon Coins on July 13, 2013 in the United States and gave 500 free coins valued $5/£3 to all users of Kindle Fire devices, who could use the coins to purchase apps, games, and in-app purchases on the Amazon Appstore. However, in 2014, Amazon started allowing all Android users in Germany, the Un... |
What were the casualties expected in an invasion of mainland Japan and how did they compare to the actual casualties caused by using nuclear weapons ? | The atomic bombs dropped on Japan killed at least 150,000, and probably more than 250,000 eventually died as a direct result of the bombings. Just to keep things in perspective, neither the bombing of Hiroshima or Nagasaki were individually as deadly as the March 9-10 1945 firebombing of Tokyo (100,000 dead). The invasion of mainland Japan was estimated to cost at least million casualties on both sides - the U.S. military ordered so many Purple Hearts that they're still handing out them today. I'm afraid I can't comment on the accuracy of their casualty predictions, but they were based on four years of brutal warfare, and both the Japanese military and civilians had proved more willing to die than accept defeat or surrender (for example: on Iwo Jima, the Japanese commander ordered his men to kill ten Americans *before they died* - not "kill ten and you can go home," or "kill ten and we'll win," but "you're going to do die and you need to kill as many of the enemy as possible;" the U.S. took 218 prisoners of the 22,000 Japanese soldiers present; civilians on Saipan and Okinawa committed mass suicide); I see no reason not to accept the military's prediction of over 1,000,000 dead and wounded Americans (and equivalent or greater numbers of Japanese) as at least a probable outcome. | [
"These casualty figures, as well as those from other island campaigns, were used by U.S. military planners to estimate that Operation Downfall, the planned invasion of the Japanese home islands, would result in well over 1,000,000 U.S. and 5,000,000 Japanese casualties. These estimates put the decision made to use ... |
Is there proof of mutation introducing new material into the genome? | How your friend put it is a bit misleading.
Mutations happen all the time. And they aren't noticeable because many don't cause any change in that gene's function. Point mutations occur in which bases (nucleotides in your DNA) are altered. There are insertions, deletions or frameshifts.. which I don't want to get into. Long regions of DNA can be copied moved around and duplicated in error. Typically this results in nothing except maybe altered expression but can lead to interesting results in a variety of ways.
Point is... mutations are noticeable when they turn genes on and off, but that's DEFINITELY not the only way they occur. You could have a mutation in you right now that causes a certain protein to have less affinity to it's substrate making it less effective.. this can be caused by a change in a single amino acid residue in that protein. An individual could spontaneously develop an enzyme that allows that to metabolize aspartame (wouldn't that be hilarious).
There is evidence for this happening (look at ecoli long term evolution experiment where the bacteria spontaneously developed the ability to metabolize citrate).
How do you think new genes come about? Typically another gene was duplicated erroneously, and then underwent many many mutations over thousands to millions of years... or less, depending on selection pressure, and viola, a new gene, with a new protein derived off old genetic code.
Sorry it's a rant, but it's a pretty open ended question. Your friend does not do justice to the complexity of mutations at an evolutionary standpoint, but then again neither do I. | [
"A molecule that allows the genetic material to be realized as a protein was first hypothesized by François Jacob and Jacques Monod. Severo Ochoa won a Nobel Prize in Physiology or Medicine in 1959 for developing a process for synthesizing RNA \"in vitro\" with polynucleotide phosphorylase, which was useful for cra... |
Why isn't the sky completely white at night? | You've hit upon a very old question called ["Olbers' Paradox"](_URL_0_).
The solution relies on the fact that the universe is not infinitely old, so only finitely many stars and galaxies are observable and they collectively subtend an angle on the sky much smaller than the full sky. | [
"The nighttime sky on Earth is black because the part of Earth experiencing night is facing away from the Sun, the light of the Sun is blocked by Earth itself, and there is no other bright nighttime source of light in the vicinity. Thus, there is not enough light to undergo Rayleigh scattering and make the sky blue... |
what causes a rolled up piece of paper to act like a spring and what other materials want to naturally return to a flat sheet when rolled | > Are there other elastic materials similar to these that would want to snap back to a flat sheet?
Sure. They're everywhere. Metal, plastic, wood, rubber, and on and on. Pretty much any common solid material will snap back to its resting arrangement when you let go, provided you don't stress it too far. Think of a paper clip: you can bend it a little bit, and it will snap back to its normal shape and clamp onto your paper. But if you bend it too far, you bend it permanently, and you won't be able to get it back to normal. You get the same effect with those cheap plastic Bic pens, or with creasing a sheet of paper.
Snapping back after stretching is known as [elastic deformation](_URL_0_). Permanent deformation after bending too far is its opposite, *plastic deformation*. The stress level where a material switches from elastic to plastic is known as the [yield strength](_URL_1_). | [
"A paper roll is threaded between two hard rollers, usually made from steel. One or both of the steel rollers has a linen pattern engraved on it. As the nip pressure between the two hard rollers increases, the pattern from the engraved roller(s) is pressed into the paper. The end result is a pattern that looks like... |
Wednesday AMA: I am Mr_Bimmler, ask me anything regarding WWII Weapons or Vehicles. | I have a question regarding the general reliability of military ground vehicles in WWII. How often would a German Tiger tank or an American Sherman need to be serviced? Could a Jeep travel thousands of miles with nothing more than filling it up with gas? Who would perform the actual maintenance if something were to fail in the field? It seems like you would need some pretty heavy duty equipment to repair a tank especially if the repair was somewhat serious. Thank you. | [
"Sonderkraftfahrzeug (abbreviated Sd.Kfz., German for \"special purpose vehicle\" or \"special ordnance vehicle\") was the ordnance inventory designation used by Nazi Germany during World War II for military vehicles; for example \"Sd.Kfz.\" 101 for the Panzer I.\n",
"BULLET::::- Captured German WW2 vehicles - A ... |
why is cyberbullying a problem? | > Basically my question is this, if you're being bullied over social networking (or even through your phone) why continue to participate?
You don't have to participate directly for it to affect you. Even if you ignore the bully, if other people in your social group are still paying attention to them, it will eventually make its way back to you. Worse, you've also left yourself in a position where you can no long directly defend yourself from any accusations.
Further, it's much easier to "cyber-stalk" (ugh, I hate phrases like that) someone. For instance, someone can set up lots of email addresses to keep harassing you even if you've blocked known addresses. They can get cohorts to continue to harass you over social media, and blocking the number of people needed to not see the harassment could leave you socially ostracized.
All of this seems to stem from young teens being in a mental place where peer acceptance is of primary importance, and absolutely *anything* will stir up drama among friends. | [
"Cyberbullying \"involves the use of information and communication technologies to support deliberate, repeated, and hostile behavior by an individual or group, that is intended to harm others.\" -Bill Belsey\n",
"'Cyberbullying' is the use of technology to bully a person, or threatening an individual online. Cyb... |
Cathedrals are large and ornate, necessitating significant investment to construct. Did Cathedrals they serve any practical purpose for the village/town/city aside from hosting religious proceedings. | There actually are a few ways that churches functioned aside from housing worshipers for Mass, but these are, of course, directly related to the church’s larger spiritual aims which took precedence in the Middle Ages. I can’t demonstrate every way that the space of the church was used at this time but I can give a few specific examples. Incidentally, both of these also relate to how churches raised funds for their own repairs and construction.
Perhaps one of the more prominent practices that became widespread during the range of dates you specified was the practice of pilgrimage in which devout churchgoers would visit the shrine of a saint or holy person—this could consist of their physical remains or some object that they had touched worn, etc—and pray in the presence of these objects so that they could for example, be forgiven for their sins, or be granted a miracle. Over time, some of these objects gained a reputation for being miraculous and thus attracted the attention of more pilgrims. This led not only changes to in the physical structure of the church itself but also alternative uses for its space. A well-known example of this is the Church of Santiago de Compostela, completed in 1211, and built to house the relics of St. James. As it was made for the benefit of pilgrims rather than local parishioners, this church had a prominent ambulatory with small chapels around it so that visitors could venerate the relics without interrupting mass [(floor plan)](_URL_0_). They could enter through the transept (side-entrance), explore the space of the church, and visit the relics located around the perimeter without disturbing the activities taking place in the nave and high altar. This practice became fairly widespread and even became the impetus for a sort of economy with hostels, pilgrimage churches and other forms of proto-tourist infrastructure popping up along major pilgrimage routes.
Another example of the popularity of pilgrimage can be seen with Chartres Cathedral [(floorplan)] (_URL_4_) [(exterior)] (_URL_1_) and, incidentally, it is also an interesting example of how major construction projects came to be funded. The relic it contained was purported to be a shift worn by the Virgin as she gave birth to Christ. This particular relic had healing powers attributed to it which made Chartres a major pilgrimage destination. In fact, during its rebuilding in 1145, wagonloads of donors arrived with food and construction materials to sustain the builders and in return were allowed to see the relics (Freeman 115). In yet another creative way of raising funds (in addition to those from bishops, church officials, and aristocratic patrons, of course), the churchmen at this cathedral played on the public’s particular interest in this relic and sent it on tour as a way to generate money for the construction of this church. This practice positions pilgrimage as a major factor in a sort of medieval proto-tourism and an influence on the economy of Europe.
Another more peripheral way that the church functioned during the medieval era was as the base for larger monastic communities. Although here the space was still used in largely the same way, it did spur the construction of supporting communities of monks whose interactions with the surrounding community broadened the ways that individuals could interact with the church. For example, if you look at the [St. Gall plan] (_URL_3_), a plan of what an ideal monastic space should look like, you can see that while the church forms the bulk of the architectural space, it also contained a hostel, guesthouse, school, and infirmary. While this particular plan was never executed, (it represented an ideal layout of space) it does show how monastic communities provided public services that could be later associated with the church.
Sources consulted:
* Charles Freeman, *Holy Bones, Holy Dust: How Relics Shaped the History of Medieval Europe*
* Carolingian Culture at Reichenau & St. Gall: _URL_2_ | [
"Because many cathedrals took centuries to build and decorate, they constitute a major artistic investment for the city in which they stand. Not only may the building itself be architecturally significant, but the church often houses treasures such as stained glass, stone and wood statues, historic tombs, richly ca... |
Why does snow accumulate in stripes? (Pic) | It is because of wind. It works like sand dunes. You start with an even accumulation, then wind blows in one direction. Imperfections in the ground surface cause some flakes to stick, and others stick to them, until all of the snow is in drifts. | [
"In the natural environment, slush forms when ice or snow melts. This often mixes with dirt and other materials, resulting in a gray or muddy brown color. Often, solid ice or snow can block the drainage of fluid water from slushy areas, so slush often goes through multiple freeze/thaw cycles before completely disap... |
how does soaking a piece of clothing in milk remove red wine stains? | You're extracting the compounds In wine by using density extraction. Milk is more dense than the wine compounds so it ends up pulling up the less dense components. Source: I'm a Biochemistry student | [
"The popular belief that carbonated water is a good remover of clothing stains, particularly those of red wine, is based on hearsay and anecdotal evidence. The dissolved gas in water acts as a temporary surfactant. There is no underlying chemical reason why carbonated water would be superior to plain water in stain... |
Monday Mysteries | Ancient Ruins | One particularly bizarre (to our eyes) archaeological feature are the mosaics found in Olmec cities like *La Venta*. [Here's an example](_URL_0_). These large patterns are made from serpentine (a kind of green stone considered to be a precious mineral by Mesoamericans). The weird thing about them is that they were buried immediately after construction. To us, this seems incredibly bizarre given how valuable serpentine was to Mesoamerican cultures. It would be like paving a large plaza in silver and then immediately covering it with cement.
These days archaeologists often say these mosaics are "ritual features." Which is a fancy way of saying that we have no idea what they were for. Most likely, they weren't meant to be seen by mortals. It was probably enough that the Olmec priests *knew* the mosaic was there so that they could invoke it in some kind of religious ritual. But what exactly this ritual was and why it needed a massive hidden mosaic face made of pure serpentine is completely unknown to us. | [
"Ancient Ruins and Archaeology is a 1964 science book by L. Sprague de Camp and Catherine Crook de Camp, one of their most popular works. It was first published by Doubleday and has been reprinted numerous times by other publishers. Paperback editions since 1972 have generally reverted to the title Citadels of Myst... |
how are my headphones playing a "ghost station"? | A nearby AM radio station is being picked up and rectified by the TV.
A simple AM receiver can be made with a junction of two dissimilar metals or a metal needle point on a crystal. I suspect the electronics in the TV are performing the rectification and the headphone cable is the antenna. | [
"Another ghost is that of Stan Andrews. He is often heard wheezing around the backstage corridors at night, checking on his ushers. Also, a boy's choir is said to haunt the auditorium. The choir played their last song at the St. James during World War II before sailing off on tour. Their ship was never seen again a... |
when using my smartphone camera why is video darker than photos for a given light level? | Exposure time.
When you take a still-shot, the camera can pause to take in a large amount of light - after all, nobody is moving around much (hopefully) and there's no rush to get another shot in within the next few ms.
When you're taking a video, however, the camera has at most 30 ms to take in light for each frame. So if the light level is low, it can't wait longer for more light, and it has to export what it's gotten so far and start taking in light for the next frame. | [
"The camera on the iPhone 5 reportedly shows purple haze when the light source is just out of frame, although Consumer Reports said it \"is no more prone to purple hazing on photos shot into a bright light source than its predecessor or than several Android phones with fine cameras...\"\n",
"There is a flash on t... |
what happens to the human body that makes it feel like cold isn't cold? | Your body can't actually sense temperature. It feels heat being absorbed or lost. So when you are losing heat your body tells you that your surroundings are cold. The more heat you lose the more you perceive your surroundings as being cold. Also, the greater the temperature differential between two things, the faster heat flows from one to the other.
You are asking about how you can feel cold in a cold temperature but then ok in that same temperature later (when you have adjusted).
This is the same thing as getting into a cold swimming pool: freezing at first but fine after you've been in it for a while. Your body adjusts by constricting blood flow in the extremities, so your skin is colder than your insides. When your skin was hotter there was a greater heat loss and you perceived it to be colder. When your skin was colder there was a smaller heat loss and your body tells you that means your surroundings are warmer (when it's really that your skin is colder). | [
"Cold has numerous physiological and pathological effects on the human body, as well as on other organisms. Cold environments may promote certain psychological traits, as well as having direct effects on the ability to move. Shivering is one of the first physiological responses to cold. Extreme cold temperatures ma... |
music equalization (as it pertains to mixing)- what's the deal? | Boosting = making a certain range of sound frequencies louder
Cutting = making a certain range of sound frequencies quieter
I'll post sample pictures in a bit.
EDIT: Here is an [example](_URL_0_).
So for me, I make hip-hop beats. When I'm making beats from sampling + chopping, I always cut the low / bass frequencies off of my samples for two reasons
1. I use other samples for bass, in which I boost the low / bass frequencies and cut out every other frequency
2. Like you said, without EQing while having multiple sources of sounds, it will sound cluttered. In my experience, when two or three of your sound sources have low frequencies which are too loud, it gives a crappy sound.
When I use synth leads, I commonly cut / lower some of the higher frequencies to make it blend better. But I pretty much cut the bass out of every track / synth / sample except for one track, which I used exclusively for bass.
Of course, with EQing, just experiment what works best for you. That's how I've learned and developed my own methods of blending different samples and basses. | [
"Equalization is used in a reciprocal manner in certain communication channels and recording technologies. The original music is passed through a particular filter to alter its frequency balance, followed by the channel or recording process. At the end of the channel or when the recording is played, a complementary... |
A balloon filled with helium goes in the opposite direction of earth's gravity. Not only does it overcome the force, but it also travels up. What would happen to a balloon in deep space? Would the helium stay put or would the balloon split and the helium go in all directions? | It is not fighting gravity. It is just lighter than the air around it. The air is pushing it up, much like air bubbles rise in water.
Space is a vacuum, so it depends on it's initial course. If the helium escaped Earth's atmosphere it would not keep 'rising'. Earth's gravity would still pull it.
But in a zero G vacuum it would travel (or be stationary) until something else acted upon it. | [
"Fully inflated, a balloon of this size would contain just over of helium. Helium's lift capacity at sea level and 0 °C is 1.113 kg/m (0.07 lbs/ft) and decreases at higher altitudes and at higher temperatures. The volume of helium in the balloon has been estimated as being able to lift a total load, including the b... |
What did a Civil War "supply line" actually look like? | So let me first explain a little bit as to what a supply line would have looked like. It would have been a massive wagon train, stretching out across the road filled with laboring beasts, sweating workers, and stench of feces and a great unwashed mass. Jostling underneath wagon covers would be every conceivable item needed for war, from ammunition and food to water, boots, hats, coats, blankets, haversacks, bayonets, swords, guns, picks, shovels, wooden planks, *replacement parts for other wagons* and literally every implement soldiers needed to stay effective in the field. Even soldiers themselves, destined for the frontline armies, used these routes to move from supply areas in the rear to the armies up front. But, like the armies of the time, these wagon trains were pinpricks in a vast arena. And they werent the only way armies transported goods.
So whats a supply line? Its best to think of them as major highways for moving men and materiel from depots in the rear to the armies up front. These supplies were usually transported in one of three different vehicles: trains, boats, or by foot power (either a beast pulling a cart, or a man carrying goods, and himself!). The Civil War was the first major conflict fought which was aided by the use of steampowered locamotives. In the realm of tactics and operations, these trains allowed armies to quickly shuttle forces across the vast American theater. They also allowed armies to reinforce and resupply quickly as supplies moved away from rear area depots to the railheads, which were the closest railway point to the front line, adjusting for the conditions of other transport mechanisms.
Railways also are the easiest supply line to understand. You have a thin ribbon of steel across which the lifeblood of armies transit. Where the railways were well developed, like in the East, transit was quick, efficient, and voluminous. But in less developed areas, or where the rail line decayed through overuse, volume quickly outstripped capacity, and prevented the free transit of supplies. Imagine what a damaged bridge, a wrecked train, or a separate rail might do to a busy rail schedule. Now imagine that same scenario in an area which was poorly developed, where that accident could block a critical passageway, and could entail rerouting traffic many hundreds of miles to reach the same destination.
Road and river traffic was more secure and less prone to accident, sabotage, and blockage. But thats not to say that there werent chokepoints and vulnerabilities across all forms of supply traffic. Each individual supply column was hard to find without the effective use of spies, scouts, and intelligence organs. Cutting a supply line rarely entailed the actual physical destruction of supply convoys and depots (though that did happen, especially in the case of raider warfare). Rather, armies would attempt to lay themselves across the enemy's supply lines, garrisoning key junctions and preventing the free flow of materiel. This would have one of three effects. If the enemy army kept on attacking, it would do so using only what goods it had with it. In that situation, most armies would simply shrivel up and die. Instead, the enemy army could pull back, attempt to outmaneuver their attacker, and reunite with supply lines. This is a dangerous move, however, because the enemy already controls some of the best routes back to base. Finally, the enemy could turn and attack, attempt to dislodge the blockage and reunite with supplies. No matter what strategy a general picked, he would have to do so with only what was available at that moment. Further, the general doing the cutting would be the one calling the shots. He controlled vital points on the map and narrowed down the possible responses greatly.
Outside of the major campaigns and set piece engagements, Raiders also plagued Union supply lines. As the Union army moved into the Confederacy, they moved away from their bases. In many cases, this led to a long and perilous supply chain which had multiple vulnerabilities. Confederate raiders, usually cavalry, would circle around the Union armies (again, pinpricks in a much larger theater) and move up the supply line. There they did as much damage as they could. Rivers were the hardest to plug up, but sunken ships and steaks could block river travel. Felled trees, burnt bridges, and roving gangs all plagued back area roads. Railways were the easiest to destroy, however, because men could easily pull apart miles worth of track, and even the removal of one rail could stop an entire train until it was repaired. All the raider's had to do was ensure that enough damage was done that could not be easily or quickly repaired. To counter this threat, the Union expended vast amounts of manpower to secure their supply lines. Between half an armies paper strength or more could be devoted just to securing the supply lines or rear areas. These forces were used in a variety of ways. Some marched with convoys to repel raiders, while others patrolled road and rail hoping to catch saboteurs in the act. In other places, they occupied garrisons to provide refuge for traveling wagons and convoys. But in every place, raider still had success. Further, rear area work could be dangerous. Confederate raiders were especially nasty, and regularly picked off isolated Union patrols.
Logistics and supply are one of the unsung elements of modern war. When we think of great military victories we rarely remember the supply clerks and logisticians who enabled that victory. Even armies which lived off the land still consumed some supplies. Men and ammunition were always in high demand. So the armies and commanders of the Civil War constantly considered where there army would get its next meal, and where it would get its next bullet. The supply side of the war was just as revolutionary, and just as important, as the major engagements.
Sources:
Russell Weigley, *A Great Civil War*
Gordon Rhea, *The Battles for Spotsylvania Courthouse and the Road to Yellow Tavern*
Martin van Creveld, *Supplying War* | [
"During the American Civil War, the firm was a seller of United States war bonds in England. With the assistance of his son, J. P. Morgan, who used the cables system to telegraph the outcomes of battles prior to their general knowledge in England, Junius was able to buy low and sell high.\n",
"The line served as ... |
how do fossils of an action or event get made? | That's not a "stone" type of [fossil](_URL_3_) but insects trapped in amber which is a [fossil resin ](_URL_2_).
The insects got trapped in the [resin](_URL_0_) from a tree and that kept them intact over the ages when it turned into amber.
[_URL_4_ article on the find](_URL_1_). | [
"Over geological time since, the rock was pushed so deep that heat and pressure hardened it much, before it came again to the surface. As a result, a common way to look for fossils in it was to break each lump with a sledgehammer, and after each blow to examine all new broken surfaces for cross-sections of bone. An... |
After we get a cut, I read that our blood vessels have to grow back at the site of the wound. Do the blood vessels always grow back in the same pattern as before, or can they grow back in a different way? | When you cut your finger your body tries to fill the wound with a mixture of totally random capillaries and collagen-rich fibrous tissue. Later, most of the capillaries will die back and the wound will contract and turn white. [Vastly more on this here](_URL_0_) starting with the angiogenesis section.
You can grow larger vessels too. A developing fetus or [a tumor](_URL_2_) will demand huge amounts of oxygen, and your body will attempt to deliver it. Sometimes [angiogenesis just goes berserk](_URL_1_) for little to no reason and starts trying to grow out of your body in a weird little red mass.
Generally speaking, your body merely tries to roughly glue you back together in the hopes that you will survive long enough to reproduce. Precision repairs are not a skill mammals have. | [
"Because the walls of the blood vessels are firmly attached to the fibrous tissue of the superficial fascial layer, cut ends of vessels here do not readily retract; even a small scalp wound may bleed profusely.\n",
"It has been hypothesized that, during both wound healing of normal tissues and tumor development, ... |
why does metal heat up so much when crushed under a hydraulic press? | Almost every metal is made up of crystals - ordered arrangements of atoms. Some metals are made of very small crystals, some are made of large crystals, and some very special metal parts can be made of a single crystal. These crystals aren't perfect - they have little atom-sized holes in them, and atoms stuck where they aren't supposed to be.
When you permanently change the shape of a piece of metal, the way it actually changes shape at an atomic level is that the holes and the misplaced atoms are forced to move around. A huge number of these holes and misplaced atoms moving around makes up the change in shape you see. But just like almost everything else, when you move these holes around, they are opposed by friction. Most of the work you put into changing the shape of the metal doesn't actually change its shape - instead, it's used to move against friction, and is wasted. That work gets converted into heat. | [
"In this process molten metal is poured in the mold and allowed to solidify while the mold is rotating. Metal is poured into the center of the mold at its axis of rotation. Due to centrifugal force the liquid metal is thrown out towards the periphery.\n",
"Metallic yielding dampers, as the name implies, yield in ... |
french politics and law | Please be more specific? Political parties or how politics work? All the laws would be challenging... do you have something in mind? | [
"French law is divided into two principal areas: private law and public law. Private law includes, in particular, civil law and criminal law. Public law includes, in particular, administrative law and constitutional law. However, in practical terms, French law comprises three principal areas of law: civil law, crim... |
who started 'high-5s' and are they universal? | [Check out this Radio Lab podcast](_URL_0_), where they ask and attempt to answer this very question. Unfortunately, I can't find a transcript, but they refer to an ESPN article called [History of the high five](_URL_1_) which might also be interesting. | [
"High 5 was founded in 1993, as a collaboration between staff of the American Symphony Orchestra (Eugene Carr and Kathleen Drohan), the New York Times (Jeanne Shanley and Sharon Yakata), and Ticketmaster (Marla Hoicowitz and Connie Fitzgerald). In 1995, High 5 appointed its first full-time executive director, Ada C... |
To what extent did resistance groups in WWII fight each other? | I am familiar in detail only with Yugoslav resistance groups. The two main resistance groups, Chetniks and communist partisans waged a civil war parallel with the war against occupying and quisling forces. Far from just occasional skirmishes this civil war in many ways determined the strategy of both, to the extent that Chetniks mostly turned collaborators as early as 1942 and almost completely by 1943 and stopped really being the resistance group. Partisans, while not turning to collaboration considered Chetniks their main rival for post-war power and acted accordingly. | [
"Resistance movements during World War II occurred in every occupied country by a variety of means, ranging from non-cooperation to propaganda to hiding crashed pilots and even to outright warfare and the recapturing of towns. In many countries, resistance movements were sometimes also referred to as The Undergroun... |
What differences, if any, were there between Soviet and Western (American, British, French) tactics in countering Blitzkrieg tactics in WW2? | Follow up. Was Blitzkrieg even a real German doctrine in WW2? | [
"During the 1930s, the resurgence of the German military in the era of the \"Third Reich\" saw German innovations in the tactical arena. The methodology used by the Germans in the Second World War was named \"\"Blitzkrieg\"\". There is a common misconception that \"Blitzkrieg\", which is not accepted as a coherent ... |
why do turtles grow as large as their tanks? | It's not totally true. Turtles will grow as big as their genetics and nutrition and other factors let them. Turtles actually have their growth stunted in an unhealthy way by being in an environment too small, not due to the physical environment alone, but also by the nutrients available in said environment. The physical environment will cause stress that will contribute to lack of growth.
Source: _URL_0_
| [
"The shape of the shell gives helpful clues about how a turtle lives. Most tortoises have a large, dome-shaped shell that makes it difficult for predators to crush the shell between their jaws. One of the few exceptions is the African pancake tortoise, which has a flat, flexible shell that allows it to hide in rock... |
how can countries be banned from the u.s. based solely on their religious majority? | > How is this possible with rights guaranteed by the first amendment?
Rights laid out in the US constitution only apply to US citizens, or people on US soil. If you're a foreign national in another country, the US doesn't have to give you any rights; that's the job of the country you're currently in.
> Does the majority of America agree with this sentiment?
Probably not the majority, but a sizable segment of the population. The 9/11 attacks, followed by the wars in Iraq and Afghanistan, further followed by ISIS/ISIL have solidified in the minds of lots of people that "Muslims are terrorists". | [
"Religion in the United States has a high adherence level compared to other developed countries, as well as a diversity in beliefs. The First Amendment to the country's Constitution prevents the Federal government from making any \"law respecting an establishment of religion, or prohibiting the free exercise thereo... |
Would a planet-sized ball of liquid water in space have a solid core of "hot ice" the same way Earth's inner core is solid? | At high pressures water will form a solid at any temperature. Wikipedia has a rather detailed phase diagram for water:
_URL_0_
Of course the specifics will vary; it'd be very unlikely for a planet to form exclusively from water, so getting a water-only core becomes difficult. | [
"Solid nitrogen has several properties relevant to its formation of rocks in the outer Solar System. Even at the low temperatures of solid nitrogen it is fairly volatile and can sublime to form an atmosphere, or condense back into nitrogen frost. At 58 K the ultimate compressive strength is 0.24 MPa. Strength incre... |
why has stop snitchin' remained so popular in low-income us populations? | People in low income situation usually have short term goals as opposed to long term goals. And in many low income areas criminal populations hold more power then government. | [
"Both in the United Kingdom and United States, they came out of social concerns about cities, poverty, immigration, and vagrancy following industrialization, as well as from a shift in society's attitude from retribution, punishing the miscreant to reforming.\n",
"Jenny, as outbreaks of measles, mumps and whoopin... |
Are Southern Chinese really Han Chinese? | Now firstly it must be made clear: "Southern Chinese" is not a single homogenous group. There are several major ethnic group that usually called Southern Chinese. These are:
- Hokkien/Fujuanese: people from Fujian. This province is the most mountainous province in eastern China. During early Han period this period are mstly out of government controls and still un-Sinicized
- Cantonese/Yue Chinese/Guangzhou people: people native from Guangdong, the province near Hongkong and Macau and to the south of Fujian. This province is less mountainous and rather easily accessible via a river route from Hunan. Even since Qin dynasty this place is already have a Chinese garrison
- Hakka: these people are recent migrant from northern China. There are good record of their migration southward and these people are undoubtedly Han
- other non-Han ethnic group sometimes also called "Southern Chinese", especially the Zhuang, who are linguistically closer to the Thais, and various Hmong/Miao people who are likely indigenous in the place
Judging from its history, the Yue/Cantonese are likely have Han descent, as it is already an important commandery since the first dynasty of China, most likely, the men from these garrisons married local women, who were as you said were of various tribes like the Baiyue.
The question whether people living to the south of Yellow river valley really Chinese is not new. In fact during the Warring States period, the State of Chu, which located in central Yangtze basin, is considered at least partially barbarian. And songs of Chu, along with its other cultural practices, were considered "exotic" by the other six warring states.
It should be noted however, that there are well-recorded migrations of Chinese from Yellow river basin whenever northern steppes nomads invaded. The migrations happened during An Lushan rebellion during Tang Dynasty, he was half-Turkic half-Sogdian. Many Chinese also fled the invasion of Jurchens invasions of Song Dynasty which later followed by the Mongols under Kubilai Khan. So saying that that Southern Chinese are less Chinese is rather inacurate based on these record of migrations.
In fact, there is this theory that it was Northern Chinese who are *less* Chinese, since North China Plains was historically invaded multiple time by barbarians from the north. | [
"The Han Chinese people are bound together with a common genetic stock and a shared history inhabiting an ancient ancestral territory for over four thousand years, deeply rooted with many different cultural traditions and customs. The Huaxia tribes in northern China experienced a continuous expansion into southern ... |
what is insomnia and why can't our brains shut off when we're excessively tired | Insomnia can be caused by many things, but one of the most common causes of insomnia is a non-functioning ability to produce the chemical that makes us begin to fall asleep.
Our brain (neurotypically) naturally makes all of the chemicals we need on a given day to function. One of them, melatonin, is produced in low light conditions when the body is laying down or comfortable, and it triggers the sleepiness that lulls us to sleep. For whatever reason (and there are many), some people's brains don't make enough of this chemical naturally to fall asleep easily.
Some causes of malfunctioning melatonin production include PTSD, rewiring what your brain expects "low lighting" conditions to look like by watching bright screens in the dark, as a symptom of other disorders like anxiety and depression, as a symptom of taking medications, from not getting enough exercise, and so on. | [
"BULLET::::- Insomnia cannot be blamed for all the deficits the patient is experiencing in his daytime life (not all problems will go away once the patient is able to sleep), this is important to know, because it takes some of the unrealistic expectations off sleep.\n",
"People with insomnia tend to excessively w... |
To what extent did the Axis power coordinate their actions/strategy in WWII? | > How much did they coordinate and plan together? Was simply being in the war and diverting resources from the Allied war effort enough?
Well the German-Italian cooperation through the war, which was characterised mostly by Germany bailing Italy out of trouble and diverting precious resources from more important theaters, is quite well known and well documented.
The German-Japanese relationship during the war was obviously quite limited simply because of the geographical factors which made direct communication and military cooperation pretty difficult. Before Operation Barbarossa started Germany and the Soviet Union were technically allies which enabled Germany to send a small naval vessel east along the northern coast of Russia all the way to the Pacific, but it was withdrawn soon after. The best example of direct German-Japanese contact was through the German U-boots, some of which managed to make their way to Batavia in Japanese occupied Dutch East India (Indonesia). But those were all minor incidents of course with no real effect on the war.
A more interesting story are the plans the German and Japanese leadership had for the Soviet Union after the war. IIRC the Japanese were prepared to join the war against the Soviet Union once Moscow had fallen. Now Hitler's plans for the Soviet Union changed quite a few times: At one points he wanted all Soviet territory west of a line going from Arkhangelsk to Astrakhan while leaving the rest for the Soviet government, while later in the war there were talks of basically dividing the whole of Eurasia between the Axis powers.
The Soviet Union would be divided between Germany and Japan, with the border starting at the most western part of Mongolia and then going north along the Yenisey river, China would go to Japan while Germany would have gotten Central Asia, and finally Japan would have gotten India and Germany Iran and possibly also Pakistan.
> Yesterday it was mentioned that the Russian-Japanese anti-aggression pact may have saved Russia from defeat in 1941. It seems odd that Japan would agree to leave Russia alone at the same time that Russia was being invaded by Germany. Did the Germans try to do anything about that?
Well there were several reasons why Japan didn't intervene in German-Soviet war.
1) **Manchurian Incidents**
Japan has always been quite poor in natural resources and this was the primary reason why they decided to take control of Manchuria in north China. Manchuria had most of the resources Japan needed to keep it's industries running without having to rely on imports from potentially hostile nations.
Anyway Manchuria borders eastern Siberia and throughout the 30s the Japanese Kwantung Army stationed in Manchuria and the Soviet forces in the far east engaged in a series of border skirmishes that cost both sides relatively high casualties, but which never escalated into full-scale war. Most of these skirmishes ended in Soviet favour primarily because of their heavier equipment and larger tanks which the Japanese had a hard time dealing with. The Japanese never really took serious steps to mend this deficiency, not because they were too conservative or incompetent, but because lighter armed infantry formations were much more efficient in the territories the Imperial Japanese Army fought in. The very hilly low-infrastructure areas of south and central China, the jungles of Indochina, Burma, Indonesia and the Pacific Islands were, contrary to the large open fields of eastern Europe and north Africa where the Wehrmacht's Panzers had free reign, not suited to armoured forces.
The last of these border skirmishes took place in early 1939 IIRC and the Japanese army leadership came to the conclusion that fighting the Soviet Far Eastern army could very well become a disastrous experience for the Imperial Army. Thus they decided to secure their northern border with a non-aggression pact. The Soviet-Japanese non-aggression pact, just like the Molotov-Ribbentorp fact, was also very much in Stalin's interest as, even though the Soviet armies had performed quite well against the Japanese, he was quite worried of Hitler's Germany and thus needed time to build up the armed forces of the Soviet Union.
So, the Japanese knew their forces were inferior to the Soviet ones which greatly decreased their desire for a war in Siberia.
2) **The Chinese Campaign**
After 1937 the Japanese also found themselves embroiled in a war in China which required considerable amounts of troops, supplies etc. The leadership of the Japanese Army expected a relatively swift victory but soon found themselves bugged down in the war with no prospect of a fast victory. Now they obviously still controlled huge amounts of territory, including most of northern China and the entire coast line, which also required considerable resources to be kept under control.
So yea, while they still maintained a somewhat considerable force in Manchuria the Chinese front swallowed a lot of the resources available.
3) **Divided Leadership**
The Japanese government was not centralised in the same way Nazi Germany for instance was, and there were several factions fighting for power. The navy and army were fierce rivals for the resources available and the leadership of both organisations had their own plans and ideas for how to win the war. The invasion of China, for instance, was not a decision made by the Japanese government, but rather by local army leadership in Manchuria who had great interests in a war with China. So once the Marco Polo Bridge Incident had occurred and the Japanese Army leaders had started sending forces into China, there was little the actual government could do about it.
Anywho after the failure of Japanese army to secure a quick victory over China, the navy faction's plan for achieving Japanese hegemony over East Asia through an attack on the European colonies to the south gained popularity. The Japanese war in China meant the European powers and the US refused to sell oil and fuel to Japan, which forced the Japanese to attack south to gain the resources they needed. The swift occupations of the Dutch East India and the other European colonies meant Japan was bogged even more down, and had yet another war to fight and allocate resources to, which made an intervention against the Soviet Union even more unlikely.
Now as to weather Hitler tried to get Japan to join the war against the Soviet Union. Yes, he did. One of the primary reasons why Hitler declared war on the United States after Pearl Harbour was he wanted the Japanese to join his war, which never happened.
| [
"During the Second World War, the Axis powers employed joint or combined operations to launch invasions in Europe and Asia. In Norway, Nazi Germany launched an amphibious invasion while the island of Crete was overwhelmed by an airborne invasion. Japan also had been successful in its Japanese imperialist wars in As... |
What set the precedent for the "campy" style of early superhero pop culture? As opposed to the gritty/realistic style we see today. | can you clarify the timelines you are thinking about? The really campy stuff doesn't start until the 60s after the pushback from the book "seduction of the innocent," (where criticism of superhero books was included along with other violent comic books) sparking a moral panic and the comics code. As a result of the code we see for example the classic campy Adam West Batman of the "silver age" (which was significantly less dark than some of the early "golden age" Batmen") before the gritty turn in the "bronze age".
My hunch is your mental model starts in the silver age which would be a mistake since the campy superheros were a reaction to earlier comics. | [
"Antecedents of the superhero archetype include such folkloric heroes as Robin Hood, who adventured in distinctive clothing, Penny dreadfuls, shilling shockers, dime novels, radio programs, and other popular fiction of the late 19th and early 20th centuries featured mysterious, swashbuckling heroes with distinct co... |
Was there ever a time and place, before alcohol regulation, where it was acceptable for children to get drunk regularly? | You seem fairly familiar with the common practice of giving smaller children beer before potable water was widely available, and the idea of "drinking water" would have seem foreign to adults and children alike.
There is another practice that might interest you, which involves giving a baby a small amount of brandy or whiskey to stop it from crying and make the infant sleep more soundly in the night. The alcohol was often dabbed on the baby's lip, put into their milk or on the tip of their bottle. This is a folk medicine practice that has been common in many cultures that continues, in some places, to today.
What your question seems to be getting at, however, is the stigmatization of alcohol and the connection between "getting drunk" and adulthood. There would obviously be a different answer to your question for every single chronological and geographic framework that might interest you. However, in general, it might be interesting to consider the types of terms you are using and the distinctions you are drawing.
For example, has "alcohol" always been a universal category? In our culture, we are able to easily define what constitutes an alcoholic beverage, but this is not a historically universal definition. For example, in some cultures, there might be fermented substances that were given to children and adults as part of religious or spiritual rituals that had the effect of "getting them drunk", but that did not have the same connotations as being an "alcoholic" or "adult" beverage.
Another term to consider is the idea of "getting drunk." You say you are interested in situations where it was "OK to provide alcohol to children for the purpose of getting them drunk." Yet you rule out situations where children were given weaker beers. Consider the effect of even a weak beer on a child. You are right in saying that water was not a commonly consumed substance because of potability, but there are examples of children being given beer (or babies being given brandy) to make them go to sleep earlier, while adults would drink caffeinated beverages like tea, coffee, or hot chocolate. The effect on the children is essentially getting them drunk, and the intention of the adults would have been to make them drowsier so they would behave better and go to bed earlier.
TL;DR: The historical conceptions of what constitutes "alcoholic beverages", what the "symptoms" of drunkennness are, and why a person would want to be drunk or want their child to be drunk, are all shifting definitions that would be very specific to a certain social, cultural, and historical context.
A cursory glance of the scholarship on the history of alcohol and alcohol culture shows that much of the research tends to be localized to a specific country or region, so it might be in your best interest to decide if there's a specific area of time period that interests you so you can focus your reading.
Some sources that stuck out to me:
Iain Gately, *Drink: A Cultural History of Alcohol,* New York: Gotham, 2008.
Eric Burns, *The Spirits of America: A Social History of Alcohol,* Philadelphia: Temple University Press, 2004.
*Altering American Consciousness: A History of Alcohol and Drug Use in the United States, 1800-2000,* ed. Sarah W. Tracy and Caroline Jean Acker, 2004.
Thomas Brennan, "Towards the Cultural History of Alcohol in France,"
*Journal of Social History*, Vol. 23, No. 1 (Autumn, 1989), pp. 71-92
Robin Room, "Alcohol, the individual and society: what
history teaches us," *Addiction*, Volume 92, Issue 3 Supplement 1.
Theresa D. O'Nell and Christina M. Mitchell, "Alcohol abuse among American Indian adolescents: The role of culture in pathological drinking," *Social Science & Medicine*, Volume 42, Issue 4, February 1996, Pages 565–578
Akyeampong E. Drink, Power, and Cultural Change: A Social History of Alcohol in Ghana, c. 1800 to Recent Times. 1996.
David G. Mandelbaum, "Alcohol and Culture," *Current Anthropology*, Vol. 6, No. 3 (Jun., 1965). (This source is a little dated, but it appears to apply a macrohistorical, anthropological lens you might be interested in.) | [
"Alcohol consumption was also used to medicate both adults and children during illnesses. Because alcohol was held in such high regard, Korean ancestors took great pains to pass down drinking customs from generation to generation.\n",
"Because of moral panic involving alcohol abuse among minors (a 16-year-old boy... |
Can bacteria survive in a freezing enviroment? | [Psychrophiles](_URL_0_) thrive at very low temperatures. Such as wiki states, temps as low as -20C. They're part of extremophiles which cover all 'extreme' environments from high heat, to acidity, and metals. | [
"Three species of bacteria, \"Carnobacterium pleistocenium\", as well as \"Chryseobacterium greenlandensis\" and \"Herminiimonas glaciei\", have reportedly been revived after surviving for thousands of years frozen in ice.\n",
"Three species of bacteria, \"Carnobacterium pleistocenium\", \"Chryseobacterium greenl... |
Does hair growth add weight? | You would get heavier as you consumed food. Hair, in this analogy, can be seen like sweat. The only difference is that it's an excretion you retain, instead of one that evaporates. | [
"Scalp hair grows, on average, at a rate of about 1.25 centimeters per month, and shampoos or vitamins have not been shown to noticeably change this rate. Hair growth rate also depends upon what phase in the cycle of hair growth one is actually in; there are three phases. The speed of hair growth varies based upon ... |
how come that in every mayor city there are hundreds of pigeons but you never see any dead ones? | Two words: Turkey buzzards. | [
"Feral pigeons often only have small populations within cities. For example, the breeding population of feral pigeons in Sheffield, England, has been estimated at only 12,130 individuals. Despite this, feral pigeons usually reach their highest densities in the central portions of cities, so they are frequently enco... |
will you explain to me the chi-square model when applied to genetics? | The chi square model is a way for people who study genes to understand probability. If two traits are inherited by a child (like blue eyes and a small nose), what are the chances they were inherited together randomly, out of all the options it could have been? The other option is that these genes are linked, meaning that they usually transfer together to the child, as in, blue eyes and a small nose will generally appear together. Research in this field is helpful for learning about genetic disorders, and what may cause them, or what the full consequences of it are.
As for the model itself, it takes data obtained from a child generation (to see how many have this pair, and how many would have mixed inheritance), and with a mathematical equation establish how likely the outcome you are studying is due to chance. In biology, usually, a variable "p" from this model establishes probability, and if it is greater than .05, the outcome was likely due to chance. | [
"The chi-square distribution is used primarily in hypothesis testing, and to a lesser extent for confidence intervals for population variance when the underlying distribution is normal. Unlike more widely known distributions such as the normal distribution and the exponential distribution, the chi-square distributi... |
Why didn't Einstein get a Nobel prize for Relativity? Was the paper on the photoelectric effect really more important? | The first thing to remember about [Einstein's Nobel Prize](_URL_1_) is that it was given for "his service to Theoretical Physics, and especially for the discovery of the law of the photoelectric effect" So it was not strictly given to him for the photoelectric effect. But to understand why that theory was highlighted above others, it is important to consider the timeline.
[Einstein published the photoelectric effect in 1905.](_URL_3_) along with several other papers, including Relativity and Brownian motion. At the time there was great interest in Black Body radiation, various spectra from excited atoms and many other phenomenon that we would now consider quantum mechanics. But at the time the complete framework was not known and these things were very mysterious. We know see the photoelectric effect as mathematically simple compared to relativity, but for many years after 1905, very little actual progress was made in what would later become quantum theory.
[Rutherford scattering was not discovered until 1911](_URL_5_) and the [Bohr model of the atom](_URL_0_) was not published until 1913, and we know it was not a complete theory of the structure of the atom. That's six to eight years of little progress, where the only known thing about quantum physics was Einstein's work. Throughout all of the quantum revolution, Einstein's work served as a 'north star' for other developments. It would take until 1926 for [Schrodinger's equation](_URL_2_) to be published, which is five years after Einstein's prize was awarded. So yes, Einstein's work on the photoelectric effect was very important and opened up many avenues of inquiry that ultimately gave us the quantum revolution of the 1920s and beyond. At the time, it was considered extremely important. While Relativity was also important, it didnt have any serious applications until the splitting of the atom in [1938](_URL_4_).
Edit: I am not a professional historian, but I do have a PhD in physics.
| [
"Through these papers, Einstein tackles some of the era's most important physics questions and problems. In 1900, Lord Kelvin, in a lecture titled \"Nineteenth-Century Clouds over the Dynamical Theory of Heat and Light\", suggested that physics had no satisfactory explanations for the results of the Michelson–Morle... |
why are real number data types such as float and double called "floating-point"? | Let's say you have 8 "spaces" to store a number. There's a few different ways you can store numbers in it:
1. Unsigned Integers. ######## lets you store numbers from 0-99999999 but no negatives or decimals
2. Signed Integers. ±####### lets you store from -9999999 to +9999999, a smaller number than option 1 but covers positive and negative.
3. Fixed Point Decimal ±XXX.YYYY only gives you -999.9999 to +999.9999. You could split it other ways, the point is that the data type is fixed when it's defined & can't be changed during runtime.
4. Floating Point Decimal ±X.YYYY \10^±Z lets you represent both positive & negative numbers from 0.0000000000001 to 9999900000. You can say that the decimal "floats" depending on the size of your Z (mantissa)
Floating point is the most common format for storing real numbers, giving a reasonable compromise between speed, accuracy & range. "Arbitrary precision" numbers that let you have any level of accuracy you want are also popular but they're generally supported by by libraries rather than CPU instructions so they're significantly slower. | [
"The floating-point form is used to represent numbers with a fractional component. They do not, however, represent most rational numbers exactly; they are instead a close approximation. There are three types of real values, denoted by their specifiers: single precision (float), double precision (double), and double... |
why is it so difficult to figure out how life actually started? | Over time, the crust of the earth gets recycled. It gets pressed down into the mantle and eroded away, only to be replaced by cooling lava.
In the past 4 billion years or so, almost all of the original crust is gone, only small portions in Canada, Australia, and Africa remain intact. That means most of the history of early life has been erased.
What's more, early life was single-celled creatures with soft body parts. Fossilization of bone and chitin is rare enough, fossilization of sort parts is **extremely** rare.
| [
"One of the major challenges in studying the origin of life has been the inability to clearly define what life is. In her investigations, Walker has used the flow of information in systems as a means to distinguish life from non-life. She used the Boolean network model, information theory, and other models to disce... |
Why does the ticking of my clock mess with the display on my TV? | Battery powered clock? Usually those use a pulsed electromagnet to advance the gearing once per second. They create a small "EMP" electromagnetic pulse. Tune an AM radio between stations, and it may pick up the one-second pulse as a click sound.
But this shouldn't affect your TV unless it has a poorly shielded (bad) video cable. | [
"A clock accompanied the look, which used GNAT (Generator of Network Analogue Time), resulting in the clock mimicked the movement of an analogue clock by moving the minute hand every second, rather than every 15 seconds as was found on previous station clocks. The counters on the clocks alternated between dots and ... |
creative commons | Whenever a person creates a work like a photo, drawing, song, poem, etc., they own the copyright to it. That means that, aside from fair use, they have the exclusive right to distribute, sell, or otherwise use it. Creative Commons is basically a way for creators to allow others to use that work, usually with certain stipulations. Some common ones is that they cannot be used for financial gain, credit must be given to the original creator, or that the new work must also be shared with a Creative Commons license.
Fair use has a couple specifics meanings, where copyrighted work may be reproduced without the owner's permission. For example, small parts of the work can be used for educational or critical purposes. | [
"Creative Commons is an organization that “develops, supports, and stewards legal and technical infrastructure that maximizes digital creativity, sharing, and innovation.” It encourages the use of protected properties online for research, education, and creative purposes in pursuit of a universal access. Creative C... |
why is it that we can't see gases in their pure form, yet we can see the shadows of gases on a sunny day? | Plenty of gases have color in their pure form.
We can see shadows on hot days because air expands and then moves. And light changes a few properties when switching between mediums, so that movement of air and change in density is what makes the light wavy (gives interference patterns).
But the gases in air do not reflect in the visible range. Which to be honest is kinda the point of us evolving this specific visible range to see in (so air wouldn’t get in out way). | [
"In principle, we cannot directly see a difference in temperature, a different gas, or a shock wave in the transparent air. However, all these disturbances refract light rays, so they can cast shadows. The plume of hot air rising from a fire, for example, can be seen by way of its shadow cast upon a nearby surface ... |
What were the relative advantages and disadvantages of varying melee weapons during the middle ages? | Since a historian hasn't responded to your question, I hope I can post these video links from a TV show that looked at "alternative" weapons such as a flail, mace, falchion, etc. :
_URL_2_
_URL_1_
_URL_0_
The host discusses some of the advantages and disadvantages of these weapons. Hope this post is OK, I can edit or delete if necessary. | [
"Later in the Middle Ages, massed archery techniques were developed. English and Welsh longbowmen in particular were famed for the volume and accuracy of their shooting, to which cavalry and poorly armoured infantry were particularly vulnerable.\n",
"For most of the Middle Ages, warfare and society were dominated... |
what does the 3-2-l mean in some automatic transmissions in cars, what are their purpose? | 3rd gear, 2nd gear, Lowest gear. Automatic switches gears automatically of course, but doesn't always give you the power you may want, so those options allow you to manually downshift and give your car more power. | [
"There are currently four different engines available, the 1.6 L \"M16A\" I4 (petrol), 1.9 L \"F9Q\" I4 (diesel), 2.0 L \"J20A\" I4 (petrol) and 2.4 L \"J24B\" l4 (petrol). The transmission choices are a 5-Speed Manual or a 4-Speed Automatic Transmission (depending on engine and market). Some markets do not offer t... |
why do my eyes become hard to keep open when i'm tired? is it the brain trying reduce stimuli and rest? | Eyes are controlled by ciliary muscles. As do all muscles, when you are tired you muscles start to become harder to use. E.G, when you lift weights, the longer duration you lift for, the more fatigued you get. Same principle. | [
"Primary reasons is eye fatigue as a result of excessive pressure on the eyes because of reading, watching TV, computer, poor lighting, etc. Some other reasons are poor posture, poor diet, lack of sleep, etc.\n",
"When concentrating on a visually intense task, such as continuously focusing on a book or computer m... |
Josip Broz Tito spoke Kyrgyz? | Tito did spend some time in what is now Kyrgyzstan during the Russian Civil War. From 1918 to 1920 he was hiding out in a village near Osh, the main city in the south of Kyrgyzstan, and eventually married an ethnic Russian from there.
However it should be noted that the region is, and was, mainly full of ethnic Uzbeks, who obviously don't speak Kyrgyz but rather Uzbek (and unlike Kazakh, I do believe Uzbek and Kyrgyz are quite different). Then there is the matter that I don't know how much interaction Tito would have had with locals, meaning ethnic Kyrgyz: they would have largely been nomadic herders at the time, largely illiterate, while the ethnic Russians (which wouldn't be many) would be more urban and literate. The Kyrgyz, like other Central Asian groups, were also rather indifferent to Bolshevism/Communism as a whole, so it further seems unlikely someone who was leaning towards that ideology would have worked close enough with the locals to learn their language. a 1953 biography by fellow Yugoslav Communist official Vladimir Dedijer also notes Tito spoke "Serbo-Croatian ... Russian, Czech, Slovenian ... German (with a Viennese accent) ... understands and reads French and Italian ... [and] also speaks Kirghiz," so he very well could have. But based on my own understanding of Central Asia and Kyrgyzstan, I would question his skills in Kyrgyz, if they did exist at all, though it would not be impossible of course. | [
"BULLET::::- 13: Yugoslav Army Colonel Draža Mihailović summons up the \"Yugoslav Army in the Fatherland\" which mostly consists of Serbs, but also includes Slovenes, Bosnians, and Croats. Mihailović treks from Bosnia into central Serbia, Ravna Gora, and issues an uprising call promising a struggle against the occu... |
if volcano eruptions are from pressure buildup, why not just drill and relieve the pressure? | That's a monumentally risky endeavor for so little reward. You could get seriously burned, possibly trigger a real volcanic eruption, and release toxic gases into the atmosphere. Furthermore, as long as the core is hot, volcanos will still erupt, and the nuclear fission of the uranium in the core will *keep* it hot for a long time to come. | [
"The sudden release of pressure causes the gases in the magma to suddenly froth and create volcanic ash and pumice, which is then ejected through the volcanic vent to create the signature eruption column commonly associated with explosive eruptions. The size and duration of the column depends on the volume of magma... |
why is it that the federal reserve can print money but america has limited inflation? | Several reasons actually. The currency(not money) that is being printed/typed into the system has not, for the most part entered the system yet. It is given to large banks (particularly the ones that are a part of or have pull with the FED) and then put into the stock market. This is done by the FED to provide collateral for the banks in exchange for them making loans that would not otherwise be made because of a high rate of default.
This money has not entered the system except for being used to buy up stocks... and you'll notice the stock market has been seeing a huge run in spite of everything else. Inflation is confined for now to skyrocketing stock prices.
Now when the loans-that-should-not-have-been-made eventually default, then the collateral will have to be used... then the currency comes back into the system everyone else uses. Now since the banks have the currency first, they get to spend it when it still has its current uninflated buying power. As the currency supply increases in the population however its buying power will decrease. People like you and me get to spend it when it buys the least.
Another reason the FED can get away with printing so much currency is the US dollars status as the world reserve currency and its use as the worlds main petrocurrency. The US government can spread the inflation across 7 billion people instead of 300 million. It's a plan that will work up until the point where the US dollar loses it's reserve currency status, or when OPEC decides it will allow people to buy oil using other currencies or commodities. If the rest of the world suddenly decides that they don't need the dollar, then all those dollars will come flooding back to the one place where it's illegal to use anything else... the US. | [
"Some protesters have argued that Federal Reserve notes (better known as dollar bills) are not actually money, because the Constitution only permits the government to \"coin\" money, and requires that such money be exchangeable for gold or silver; therefore, printed bills are instead symbols for use in bartering, a... |
How did the titles of "Roman Emperor" and "King of the Franks", both held by Charlemagne, become separated? | So [this excellent post](_URL_0_) a week ago by /u/idjet explains the circumstances of the passing on of Charlemagne's imperial title, as well as whether he intended to do so or not.
However, whatever the details were, after the division of the empire after the death of Charlemagne's surviving son Louis the Pious, the title was passed to Louis' son Lothair because in the triparte split of the empire, Lothair possessed the core Frankish lands in middle francia as well as Italy and Rome. And since it was understood that in order to be emperor, one needed to be in possession of Rome, Lothair was thus designated the emperor.
This continued on after his death with his son Louis II, who was emperor even though he possessed no part of the former frankish homelands, and only retained the title King of Italy. Though the empire, the imperial title, and the frankish royal title would be reunited again under Charles the Bald and Charles the Fat, after the latter's deposition, you would see a similar situation as to what happened with Charlemagne. The various component kingdoms of the Carolingian Empire would be divied up (although this time the inheritors would not necessarily be Carolingians), and it only took someone in possession of the title of King of Italy to be crowned emperor (although not all kings of italy would be crowned emperor). And they would only be crowned because there was a need for legitimation or other political concerns, local entirely to Italy, as opposed to the rest of the former Carolingian Empire.
Which is how, the titles of "King of the Franks" and its successor titles, King of the West Franks (West Francia), Middle Franks/Francia (Lotharingia/Lorraine) and East Franks/Francia came to be split from the imperial title. | [
"For this reason, Charlemagne, the King of the Franks and King of Italy, was crowned Emperor of the Romans (\"Imperator Romanorum\") by Pope Leo III, as the successor of Constantine VI as Roman Emperor under the concept of \"translatio imperii\". The Eastern Empire eventually relented to recognizing Charlemagne and... |
why acceleration is constant in a vacuum, and an airplane would fall at the same velocity as a tennis ball? | Because in a vacuum a moving object has no resistance acting on it. Clarify the second part of the question please. | [
"If a projectile, such as a baseball or cricket ball, travels in a parabolic path, with negligible air resistance, and if a player is positioned so as to catch it as it descends, he sees its angle of elevation increasing continuously throughout its flight. The tangent of the angle of elevation is proportional to th... |
what is social engineering? | Social structures can be 'hacked' just like physical and digital structures can - and it's often easier to approach an intrusion problem from this standpoint.
Actually hacking into the DMV database is a relatively difficult task. However, pretending to be an IT consultant and tricking those with passwords to the database into revealing them is comparatively easy. That no-tech-skills-required approach is 'social engineering'.
As for being a science, no. It's no more a science than selling used cars is a science. It's mostly just being able to interact with people effectively.
In terms of a negative context, social engineering is fundamentally about tricking people into doing what you want them to do. While it often involves a degree of research - you need to know who the gatekeepers are before you can trick them into opening the gate - it's little different than any other con game.
From the standpoint of the hacker community, it's also often considered a 'lesser' form of hacking. Hacking is, in some ways, a competitive intellectual activity. It's not just enough to intrude into a privileged system but you have to do it in a clever or skilled way. Hacking a shipping database to have the next delivery to your local supermarket directed to your doorstep is cool. Throwing a brick through their window at night and carrying off that delivery is not. | [
"Social engineering is a discipline in social science that refers to efforts to influence particular attitudes and social behaviors on a large scale, whether by governments, media or private groups in order to produce desired characteristics in a target population. Social engineering can also be understood philosop... |
how do celebrities tweet and reply to other celebrities on twitter considering there are thousands of people tweeting them as well? | There are services and software you can use with twitter to let you know when a certain user tweets you or posts a tweet, chances are most celebrities don't even see their fans tweets unless a pr person alerts them to one they should reply to. | [
"The most popular United Kingdom celebrities on Twitter come from television with people like Stephen Fry and Jonathan Ross being amongst the most popular British celebrities on the site. Fry's success on Twitter is credited with being the same person on Twitter that he is off Twitter.\n",
"Twitter is also used b... |
How did the wives of roman soldiers learn of their husbands deaths? | Alrighty, 'cause I just noticed this thread, I'm going to go ahead and do a writeup on this. I'm going to try to address all of the questions already asked in the body, so bear with me (barring the question that's outside the purview of my specialty).
First, I'm going to confirm a simple fact. Roman soldiers were not allowed to get married. That changed depending on rank, but the rank and file were not legally allowed to get married - so there weren't any wives at home that had to get that painful letter (for the standard legionaries). However, men are men, and people are people- and the vast majority of the time a legion was just garrisoned in a province. People in that situation, naturally, develop relationships, and those relationships were tactfully ignored by the officers, who totally understood the situation these men were in. They weren't allowed to get married, but they WERE in love - the great rock and hard place argument :) The thing about being in the Legion (I'm assuming we're talking about the Principate here - that would be ca. 0-300ish CE) was that once you were in, it was a 25 year commitment. While you got great benefits, those 25 years could be hard on a man - especially when that man wanted a family. So, the natural solution? "Civil unions."
Those civil unions were essentially the same as marriage, just without any of the legal entitlements that they would otherwise have- so pretty much, it was marriage. Just without the government recognition. Confusing, eh? :)
One big issue with this was that many of the women that the Romans took to wife were natives of the area they were garrisoned in, or even former slaves (The soldier would buy them and promptly free them). Those families would, of course, also go on to have children - and those children called themselves "*in castris*" - or "born in the camp." They generally went on to join the military, just like their parents, and there's a tombstone outside the fortress of *Legio II Augusta* that commemorates a woman, her soldier son, and her husband. The monument itself was erected by her daughter.
However...the unfortunate bit is that there are always those damn legalities. We have evidence of seven cases that deemed children born during their father's terms of service to be "illegitimate." Didn't matter if they were citizens or anything - if they were in the legions or *auxilia*, that child had no claim to be the heir of their father, his will, etc. Same with the wives - except the wives *also* couldn't get their dowries back (Legal wives could).
Now, on to the husband dying! It's hard to say exactly how they were informed - however, if they were one of these quasi-wives, it would have fallen to the man's tent group (*contubernium*) - who would have known about the quasi-marriage - to let the woman know. The wives either lived right outside the fort in the *canabae*, or even in the room with the rest of the *contubernium*. A quick note here - privacy wasn't such a huge deal until recently, most especially regarding situations with large families (All in one room) or in these cases (8 men in one crowded room - it would have been relatively common for at least one to have a woman in there with him).
I do want to stress though (regarding another question in this thread) that the legionaries still maintained strong family ties with both their quasi-wives and their "illegitimate" children. The vast majority of tombstones near military encampments are commemorations by the wife or "unrelated heirs" (coughchildrencough). We have multiple declarations by these soldiers declaring these children to be their heirs, the children are explicitly mentioned in the wills, and provided for them. As for notifying family (such as parents, siblings, etc), I have no source on that one - I can only speculate that the *contubernum* would send a letter to them as well.
---
Finally, onto one last question that was addressed - "Could officers and commanders be married?" The answer to that is **yes....ish.** The senatorial and equestrian officers were certainly allowed to be married. Legionary centurions were also exempt, however, we have no sources regarding the auxiliary centurions or the decurions - we can *assume* that they would also be exempt, but it's no guarantee. Their wives and children would also have accompanied them, but they (The senators and equestrians, at least - the centurions could and did) were forbidden from marrying *local* women. The senatorial and equestrian officers also spent far less time in the military - it was generally just a step in their career.
Now, finally, on to what happened when a soldier died! One of the (many) deductions from the soldier's pay was a contribution to a "burial fund" that was organized per century. It wasn't much - it would only cover the costs for a basic funeral - but it was something. I'll go ahead and just quote straight from Goldsworthy for the next bit:
> A funeral procession, carrying the corpse on a couch, would leave the fort or camp, for like many contemporary societies the Romans insisted that burial take place outside the settlement. Once outside, and often on a site running alongside the main road leading to the fort, the corpse would be laid on the couch on top of a funeral pyre, There it would be burnt and, once consumed by the flames the ash of both corpse and pyre gathered into a funerary urn, made sometimes of marble or metal, but most often of glass or pottery, which was then buried. Around the grave site the mourners took part in a funeral banquet.
> [...] The chief mourners were a man's comrades and, as the practice of taking an unofficial wife became widespread, his family. It is doubtful that the burial club paid for more than the most rudimentary of markers for the grave, but many soldiers set aside money to pay for expensive stone monuments. Many tombstones state that they were erected by a man's heirs in accordance with his will.
I sincerely hope that helps :) If you have any more questions, please don't hesitate to ask them!
**Sources:**
-Goldsworthy, Adrian - *The Complete Roman Army*
-Scheidel, Walter - [*Marriage, families, and survival in the Roman imperial army: demographic aspects*](_URL_0_)
| [
"Caesar provides an example of the subordinate position of women: according to him, men had the power of life and death over their wives, as they did over their children, in a similar manner to the Roman pater familias. If the head of a high ranking family died, his relatives would gather and interrogate the wives ... |
Would it ever be possible to create a mirror that reflects 100% of the light it's exposed to? | Yes, but not in the traditional sense.
Mirrors are normally made of a polished metal surface covered by glass. This kinds of mirrors are theoretically unable to achieve perfect reflection.
It is possible to achieve perfect reflection using total internal reflection, and it has been done before. It wouldn't work like your traditional mirror because firstly, it only works for certain wavelengths of light and certain angles. Secondly, TIR only works when light travels from media with a higher refractive index to a lower one. This means that a flat mirror will not work. | [
"Almost any dielectric material can act as a perfect mirror through total internal reflection. This effect only occurs at shallow angles, however, and only for light inside the material. The effect happens when light goes from a medium with a higher index of refraction to one with a lower value (like air).\n",
"A... |
why are there airpockets in underwater caves that are clearly under sealevel? | The caves may have a hidden opening or cracks somewhere to allow air in. If not the air pockets may come from methane or carbon dioxide from degradation of organic matter on the sea floor or some kind of natural gas pocket. It's unlikely that any air pockets in an underwater cave would be breathable since sunlight would be needed for plants or algae to make oxygen.
Another theory could be that the cave was above sea level at some point and the rising ocean could have caused air to be trapped in the cave. | [
"BULLET::::- This lack of bubbles allows wreck divers to enter enclosed areas on sunken ships without slowly filling them with air, which can accelerate rusting, and is also an advantage in cave diving if there is loose material on the ceiling which can be dislodged by bubbles, reducing visibility.\n",
"The cave ... |
How are the causes of airplane crashes identified? | Well, from the "something broke in the air" perspective; fractures that occured in the past look a lot different than fresh ones, and fractures from impact look a lot different than fractures [from other causes.](_URL_1_)
Imagine a crack in a steel part, for example. If the crack slowly propagates until the part snaps, you'll have a fracture that is half old and rusty, half fresh and clean. The rusty half will probably be all ratty as well, while the final fracture will be relatively straight and clean.
Also, some types of damage look very unique. For example, you might see some [fretting](_URL_0_) at the location of a fracture. That fretting would be highly suspect as the cause of the failure. If failure of that component led to a loss of control that matches the final moments of flight then you can be pretty sure that's the cause of the accident. Note, the picture is from a shaft in a helicopter that was removed prior to breaking. This particular failure mode is apparently quite common for this part.
There's a zillion things like that, and it would take a whole book (for example, ["why things break"](_URL_2_)) to explain all of them, but the long and short is that damage from an impact does not look like damage that occured before impact.
| [
"A first report by the Federal Bureau of Aircraft Accidents Investigation was published in May 2013. It listed the known facts of the accident without identifying a cause. The cause of the accident was still unclear .\n",
"United States civil aviation incidents are investigated by the National Transportation Safe... |
To what extent was Stalin responsible for the Korean war? | According to Halberstam's "The Coldest Winter" page 49
"Stalin was playing a delicate game, flashing a half-green, half-amber light on the invasion."
Halberstam later states that Stalin gave Kim permission, but kept his involvement to a minimum and told Kim to rely on China for any material support. There's later an assertion on page 345 that Stalin had promised air cover to Chinese troops, but reneged on his promise.
This sounds like the mainstream theory, I'm unaware of any alternate theories.
EDIT: Spelling | [
"Despite the expenses and regardless of who paid them, it must also be said that the Korean War provided approximately thirty thousand Soviet military personnel valuable experience in waging local wars. The conflict also allowed the Soviets the opportunity to test several new forms of armament, in particular the Mi... |
What would happen if we allowed exotic animals to go extinct? | > What would happen if we didn’t protect exotic animals and have laws on hunting and conservation?
Its not just exotic animals that we protect, every country protects animals and their ecosystems within their borders. Also, the USA does not regulate how foreign countries manage their resources, ecosystems or endangered species. There is [CITES](_URL_0_) which is an international organization that regulates the transport of endangered plant and animal products across borders. Despite this many millions of plants and animals are being illegally transported for the pet-trade, food, or medicinal products. There is also the [IUCN](_URL_2_) which helps conduct studies and creates reports on animals. It is the governing body that decides if animals should be classified as endangered on a global scale.
Once and animal or plant is listed governments who signed the treaty must put in steps to save or mitigate the effects that are causing the species decline. Not only does this create jobs, (scientists, policy makers, enforcers) but it often preserves the local ecological system. Because animals need habitats, saving them often means that some chunk of land also needs to be preserved. This can be good and bad for people.
**The Good**
We are part of this world, and this world provides many services for us. The Earth cleans our water, it filters our air, provides us food on scales we cannot begin to imagine. Some have tried to put values on these services and often it amounts to hundreds of billions of dollars in saved expenditures. Often by preserving local ecosystems the surrounding land becomes more fertile, the water cleaner and so on. This is especially important in countries where they may not be able to afford equivalent technologies on larger scales. Also, animals can bring in ecotoursim and promote cultural identity. These are all positive thinsg that can create jobs and bring money to improvrished regions.
**The bad**
In certain regions resources are very scarce and people fight over them. Parks where they exist sometimes hurt the people because they no longer have access to things they need like fuel and food. Education is key here - teaching people how to live sustainably in the forests using their local customs and traditions. Its important that conservation just doesn't come from governments in a"top down" fashion, but also in a "bottom up" - where communities and individual people understand the importance of conservation and see how it can improve their lives.
> Is there still a natural eco-balance that animals like elephants, tigers, and others are helping maintain?
Yes, each animal and plant has its place in the ecosystem. They all contribute to the eco-balance but in different ways. That being said plants and animals to naturally go extinct. Sometimes if you remove just one [keystone species](_URL_3_) the whole ecosystem goes to the shitter. Example: sea otters in the pacific northwest. [Foundation species](_URL_1_) build an ecosystem up from the bottom, like plants, they provide the basics - food for herbivores, which in turn support carnivores. Removing these species - such as cutting down a forest, destroys that habitat for every other species within it. Thus different species have different effects. If we managed to kill bees we would be pretty fucked - no more fruit, mosts woods, and fibers etc. We would have to live on wind-pollinated plants like the grains.
> Do all animals play a role in keeping the earth safe and habitable or would the extinction of some species not have any serious consequences?
Of course loosing a few species is ok, this is natural. Extinction is natural. One day we too will go extinct. However its the *current rate* of extinction that is alarming. When so many species are threatened, ecosystems weakened by hunting, logging, burning, overfishing, wars, pollution, and other destructive human habits - the survival of some of our human communities is at stake. So while having the amur leopard go extinct in china may not seem like a big deal it represents a systematic abuse of the natural world on our part. It destroys our quality of life and hurts us. We could permit a few species to go extinct, in fact many have already (like the dodo, or the passenger pigeon) yet we are all still here. But these extinction events weaken ecosystems, the next extinction event does the same until the ecosystem supports almost nothing and is only a vestige of what it once was.
TL;DR every animal is important, because each animal has its role to play. Either in its ecosystem or saving that ecosystem, or in improving our quality of life. | [
"Despite their relatively small size and secretive nature, some species may be susceptible to extirpation, mainly due to habitat alteration and introduced feral animals. The Navassa Island dwarf boa, \"T. bucculentus\", has not been seen for 100 years and is believed to be extinct.\n",
"A 2010 report said that th... |
how does cold air reach body temp in your lungs so fast? | There are small sacs in your lungs that bring the incoming air in close contact with your circulatory system. This quickly brings the air close to body temperature , as well as enabling the transfer of oxygen and carbon dioxide. | [
"BULLET::::- The wind chill factor measures the effect of wind speed on cooling of the human body below 10 °C (50 °F). As airflow increases over the skin, more heat will be removed. Standard models and conditions are used.\n",
"In the lungs a temperature of 37 °C and 100% relative humidity (RH) is the ideal condi... |
If I have a system of mirrors that makes 300 million meters could I see the speed of light? | Yes you can. This is used to determine the speed of light experimentally (There is an easy demonstration using fast rotating mirrors, look at how Fizeau and Foucault measured it in in the 19th century).
You can also do an easy experiment if you have access to an oscilloscope. An electromagnetic signal moves at the speed of light. In a standard 50 Ohm coaxial cable this is about 60% the speed of light in vacuum. So if you send an em pulse from e.g. a pulse generator to two channels of the oscilloscope, one via a short cable, the other via a cable 10 m longer, you will see a time difference of the signals of t = s/c = 5x10-8 s = 50 ns, which is easily observable. Make the cable twice as long, the time difference doubles as well. | [
"Another more accurate measurement of the speed of light was performed in Europe by Hippolyte Fizeau in 1849. Fizeau directed a beam of light at a mirror several kilometers away. A rotating cog wheel was placed in the path of the light beam as it traveled from the source, to the mirror and then returned to its orig... |
have humans created a new species? (via selection) | Using the biological species concept (which I assume, based on your question, is your framework), we have only created one to my knowledge: [Drosophila synthetica.](_URL_0_)
If you use the morphological or phylogenetic species concepts, we have created buttloads. | [
"Humans have created a wide range of new species, and varieties within those species, of both domesticated animals and plants. Other human activity also impacts evolution. This has been achieved in a very short geological period of time, spanning only a few tens of thousands of years, and sometimes less. Maize, \"Z... |
why do some foods contain insect parts? | If you have an open vat of tomatoes, say at the ketchup making plant, bugs are going to get into it. Then you take all those tomatoes and put them in a machine that pulverizes them. The machine doesn't differentiate between bugs and tomatoes, it just makes juice out of whatever is in the storage container.
Then that gets heated up (or treated with acid/caustic solutions) to kill anything that could be harmful to people, bottled, and sold.
There isn't some magic force-field that keeps bugs out of the food you eat pre-processing, and most mass produced foods will not bother to remove them since they pose no health risk. | [
"Insects as food or edible insects are insect species used for human consumption, e.g., whole or as an ingredient in processed food products such as burger patties, pasta, or snacks. The cultural and biological process of eating insects (by humans as well as animals) is described as entomophagy.\n",
"In some cult... |
why are serif fonts "easier to read in long paragraphs of text?" | There's actually no conclusive study on this that shows that serif fonts are genuinely easier to read than san serif fonts.
The idea is that the extra markings make a letter more immediately distinguishable from another letter. By having more angles on a letter, there is sharper contrast to one another and to the white background that offers a more visually interesting stimulus than the rounded letters.
[Studies show that people overwhelmingly prefer them subjectively, and that comprehension increases in serif fonts](_URL_0_). But there's no data to support they're actually "easier on the eyes" in any form.
If they are, it's a slight variation that you can think of in terms of something being easier to read for the eyes when it's in sharp forcus than when it's slightly blurry. The extra angular stimulus may produce a similar effect to additional "focus." | [
"Serifed fonts are widely used for body text because they are considered easier to read than sans-serif fonts in print. However, scientific study on this topic has been inconclusive. Colin Wheildon, who conducted scientific studies from 1982 to 1990, found that sans serif fonts created various difficulties for read... |
can sound waves create other sound waves? what would those sound like? | Absolutely! Sounds waves are just a vibration, and cause other objects to vibrate as well. Primary waves create what are called overtones and harmonics as they interact with the air and surrounding surfaces.
If you go to a piano and play one of the lower notes loudly and hold the key down, you will hear other, higher strings vibrating, highlighting the overtones of the primary wave. It's a cool effect!
| [
"Sometimes sound waves at ultrasonic frequencies can be used to levitate objects, thus creating no sound heard by the human ear, such as was demonstrated at Otsuka Lab, while others use audible frequencies. There are various ways of emitting the sound wave, from creating a wave underneath the object and reflecting ... |
What warcrimes did the Dutch commit in the Indonesian Independence war in 1945-1949 | The Dutch historiography and research into war crimes conducted by the Dutch army during the Indonesian independance war is not very well researched. This because it was 'actively forgotten' by the Dutch governement in that no serious research was conducted , people involved were encouraged to remain silent about it and the image of The Netherlands as tolerant and 'clean' colonists was protected.
At first the intervention was seen not as a war, but as an action against internal terrorists. The term 'politionele actie' was used, for a very long time, to avoid speaking about the Dutch intervention as being a war. Veterans were asked in loyalty to the Dutch Queen to 'keep all secrets inside the Dutch army'. And any appeal for political introspection and claims for reparations were subdued. A striking example is liberal politician and member of the Foreign affairs committe of the Tweede Kamer claiming as late as 2007 that: 'The Dutch military personel have generally behaved with utmost decency... No excuses shall be made' he even likened the proposed reparations to 'The Dutch paying reparations to the king of Spain for cuelties conducted during the Dutch independance war' (this is a comparison of striking sarcastic nature).
Most current research is centred around the Rawagede-debate. Rawagede was a massacre of over 430 indonesian males on 9 december 1947. The photos of this masascre were published in the NRC Handelsblad in the '90s and sparked the historical research into Dutch atrocities. Dutch historian C. Lorentz says that this might far from be an isolated case as 'Rawagede might be the tip of an iceberg'. Aside from Rawagede, though, not much of this history has been researched yet.
I am not involved in said research, as my thesis is on pre-war Dutch-Indonesian history, so I can't really comment on the role of the MarBrig or your great grandfathers regiment. I can give you some pointers to start looking. The books *Generaal Spoor: triomf en tragiek van een legercommandant* by Jaap de Moor and *De brandende kampongs van Generaal Spoor* by Remy Limpach are a good starting point. You can find them at the Amsterdam NIOD, the Dutch research institute for War and Genocide studies. The NIOD also employs most researchers that are currently working on the case of Dutch atrocities in Indonesia and has a huge archive. If you ask around there might be people who can point you in the right direction of finding more about the history of your great grandfather. The NIOD has a library that is open to the public and contains most books that will be relevant to your case.
I hope that helps you on your way. Good luck!
Sources:
* Lorenz, C. (2015). 'De Nederlandse koloniale herinnering en de universele mensenrechten'. *Tijdschrift voor Geschiedenis*, 128(1), 109-130.
* Eickhoff, M. (2015). 'Weggestreept verleden: Nederlandse historici en het Rawagededebat'. *Groniek*, 45(194).
| [
"The Japanese invasion and subsequent occupation during World War II ended Dutch rule and encouraged the previously suppressed Indonesian independence movement. In May 1940, early in World War II, the Netherlands was occupied by Nazi Germany. The Dutch East Indies declared a state of siege and in July redirected ex... |
how does the bar exam work and who governs it? | In the United States, each individual state has its own bar exam, and it is generally administered under the authority of the state's highest court. For example, the Illinois bar exam is administered by the Illinois Board of Admissions to the Bar (IBAB), and IBAB is seven lawyers appointed by the Illinois Supreme Court. New York has the New York State Board of Law Examiners, which is five lawyers appointed by the New York Court of Appeals (New York's highest court).
Passing the bar exam is generally a requirement for becoming licensed to practice law in that state, but there are other requirements, too, such as graduating from law school, and passing an extra-detailed background check, which may be called a "character and fitness" evaluation.
State laws vary, so most states have a unique set of questions for at least part of their exams. However, there is also a "Uniform Bar Exam", which some states use part or all of. Bar exams can take an entire day, or even multiple days.
If you pass the state's bar exam, and your application shows you meet all of the other requirements, you can be sworn in as an attorney and practice law. | [
"The bar examination in most U.S. states and territories is at least two days long (a few states have three-day exams). It consists of essay questions, usually testing knowledge of the state's own law (usually subjects such as wills, trusts and community property, which always vary from one state to another). Some ... |
Is it possible to estimate the cost of constructing one of the great pyramids (adjusting for inflation)? If so, how expensive of a project was it? | Ancient Egypt didn't have a monetary system until 2000 years after the pyramid's construction so it is probably better to use work hours and the cost of employing workers as a comparison, especially because the value of today's money is heavily warped compared to a barter system.
--------------------------------
**How many people worked on the Great Pyramid?**
Excavation of the pyramid town south of the Sphinx have revealed galleries that could house about 4000 workers. At the start of the construction however it is likely that several more thousand workers were hired to clear the perimeter of sand and smooth the bedrock, and complete the first few layers of the pyramid.
To provide for those workers a brigade of tailors, bakers, sandal- and wig makers, butchers, and many other people that transported or provided goods and helped logistically.
Workers were well cared for, and received benefits such as:
Medial care, tax exemptions, cloths and housing, food for their families, usually 1 day off per week (5 day weeks), beer (which was a very common drink with low alcohol content), beef (cows had to be imported from other parts of the country), wigs, makeup, all kinds of fruit and vegetables and of course bread, amongst other things.
All in all most of the time about 6000-8000 people worked directly or indirectly on the monument's construction.
--------------------------------
**How long did it take?**
The Great Pyramid was not the only thing being constructed by those workers. A mortuary temple and a valley temple with a harbor had to be built with a causeway of several hundred meters connecting them. In addition 3 Queen's Pyramids, a satellite pyramid, 12 mastabas that were later joined and expanded to 8 twin-mastabas and giant perimeter walls had to be built as well.
The majority of stones was local limestone that came from the east side of the plateau, only a few hundred meters away from the pyramid. Under 1% was hardstone such as basalt and granite that was imported from upper Egypt and the rest, the white limestone was imported from Tura in the north-east.
In total about 2.5 million m³ of local limestone had to be quarried and transported. In contrast to popular believe the vast majority of those stones were not neatly cut, square blocks but stones of all sizes and shapes. We know this because Vyse blasted a hole into the south side of the pyramid.
To cut (mostly stone tools were used) and transport 1m³ of the local stone approximately 40-80 work hours had to be spent depending on the stone and location (2 people quarrying for a day, 2 trips á 1 hour with a 10 man team to transport).
Including the other stones it would have taken 150,000,000-200,000,000 work hours to complete the pyramid and the adjacent buildings.
We don't know how many people only worked seasonally and how many all year, so completing the pyramid would have taken between 10 and 20 years with an average of 5000 workers (assuming 10 hour days, 150 or 300 days of work a year).
----------------------------------
**How much did it cost compared to today?**
Only a few percent of the workers had to be highly skilled (architects, stonemasons, foremen, etc.) but most workers were well cared for (even by today's standards).
Since it was a royal project the Pharaoh didn't have to pay for land and most resources but they still have a value. To translate that value to modern money is difficult however since goods like grain can not be stored and easily exchanged as money on a bank account can.
But to put a price on it: Assuming 5% of the workers were highly paid: 50$/h and the rest moderately well: 20$/h it would cost around **5 billion dollars** to pay for ~200 million construction work hours and the people providing for them. | [
"One mystery of the pyramid's construction is its planning. John Romer suggests that they used the same method that had been used for earlier and later constructions, laying out parts of the plan on the ground at a 1-to-1 scale. He writes that \"such a working diagram would also serve to generate the architecture o... |
if i rinse out a dish right after using it and there's nothing on it, is it fully clean or do i still need to use soap? | Come on, man. Soap. | [
"Hand dishwashing detergents utilize surfactants to play the primary role in cleaning. The reduced surface tension of dishwashing water, and increasing solubility of modern surfactant mixtures, allows the water to run off the dishes in a dish rack very quickly. However, most people also rinse the dishes with pure w... |
What is the cost of the extinction of individual species? | Answering that question requires two other questions be answered: "How important is the niche this organism is in?" and "How well can other animals fill in that niche?" Many species are more critical to the survival of an ecosystem than others. For instance, in the Southern US gopher tortoises are suffering huge losses, and as a result many other small ground-dwelling animals are also suffering, because gopher tortoise burrows were used by a variety of them for shelter. | [
"It's estimated that, because of human activities, current species extinction rates are about 1000 times greater than the background extinction rate (the 'normal' extinction rate that occurs without additional influence) . According to the IUCN, out of all species assessed, over 27,000 are at risk of extinction and... |
how likely is it that earth is the only planet with living beings, and that humans are the only species that have the intelligence to speak, create, develop etc? | We don't really have great way to actually put a number to it, but the general consensus among scientists is that it's essentially a certainty that there *is* other intelligent life out there. Based on our current knowledge of exoplanets, it's estimated there as many as *40 billion* Earth-like planets in our galaxy alone, and at absolutely minimum, 176 billion galaxies in the observable universe (although actually estimates put the number at an astounding 2 trillion). There's nothing special about life on Earth as far as we can tell, so the odds of it not happening somewhere else in the trillions upon trillions of other worlds out there is just mind-bogglingly infinitesimal. | [
"It may be that while alien species with intelligence exist, they are primitive or have not reached the level of technological advancement necessary to communicate. Along with non-intelligent life, such civilizations would be also very difficult for us to detect, short of a visit by a probe, a trip that would take ... |
what is mthfr gene mutation? | The MTHFR gene has the instructions for the body to build an enzyme with a really long name. An enzyme is a protein that helps the body perform chemical reactions. This particular enzyme helps make methionine, one of the building blocks of proteins, and helps the body to use vitamin B9 (also known as folic acid).
A genetic mutation is when the gene's instructions are different from that of the regular version of the gene. In other words, the instructions are misspelled. Mutated genes often cause the body to make less effective versions of the corresponding protein. In MTHFR's case, this means that the body produces enzymes that aren't great at making methionine and utilizing vitamin B9.
There are multiple medical problems that can result from MTHFR mutations, including increased risk of blood clots and birth defects of the nervous system. | [
"The MTHFR nucleotide at position 677 in the gene has two possibilities: C (cytosine) or T (thymine). C at position 677 (leading to an alanine at amino acid 222) is the normal allele. The 677T allele (leading to a valine substitution at amino acid 222) encodes a thermolabile enzyme with reduced activity.\n",
"At ... |
the handicap hypothesis/principal in sexual selection | Rich person wants to convince a potential mate that he/she is worth mating with. Rich person has so much money that they can afford to spend much of it on frivolous material goods that may actually decrease their ability to survive (dangerously fast car). This signals to a potential mate that they are exceptionally worth mating with.
The rich person is handicapping themselves (increased potential to die), but doing so in order to increase sexual desirability. | [
"Several mid-level evolutionary theories inform evolutionary psychology. The R/K selection theory proposes that some species prosper by having many offspring while others follow the strategy of having fewer offspring but investing much more in each one. Humans follow the second strategy. Parental investment theory ... |
the significance of platonic solids, what makes them different from the other shapes? | They are polygons (3D shapes made up of flat surfaces joined together) for which:
* the faces are identical in shape and size
* the faces are regular polygons (so all their angles equal and all their sides are equal)
* the same number of faces meet at each vertex (corner) of the polygon
* the polygon is convex (it doesn't have any indentations)
They are interesting because there are only five such polygons:
1. Tetrahedron made up of four equilateral triangles
2. Cube made up of six squares
3. Octahedron made up of eight equilateral triangles
4. Dodecahedron made up of twelve regular pentagons
5. Icosahedron made up of twenty equilateral triangles | [
"\"The Platonic Solids\" was inspired by Plato's conception of the five classical elements: earth, air, fire, water, and ether. In Plato's work \"Timaeus\" (ca. 350 BCE), the five forms of matter are related to elemental solids and shapes (the cube, the octahedron, the tetrahedron, the icosahedron, and the dodecahe... |
Why do depictions of American Indians never show men with facial hair? | You may be interested in the older post:
* [Native Americans generally didn't have beards. Do we know what they thought of the bearded and mustachioed Europeans and their decedents?](_URL_0_)
Many groups plucked facial hair, with wooden or shell or even bronze implements. Others apparently singed hair off. In some groups, certain types of people did not remove hair—people in mourning among the Yurok, or possibly the old among the Aztecs, to give two examples. | [
"Some consider Williams' portrayal of American Indians to have been offensive. His use of a stylized headdress was often referenced as the reason for offense, as the headdress is a sacred, central cultural item for many tribes.\n",
"H. Harris, publishing in the \"British Journal of Dermatology\" in 1947, wrote Am... |
why drugs companies give half the people placebo's and half the people the actual drug when testing | Lets say you give 10 people a new drug and 5 of them get better/improve, you might think that 50% of the people who take the drug get better.
If instead, you give 10 people the drug and 10 people a placebo and 5 people from each group get better, than you know that the drug isn't (neccessarily) causing the improvement. | [
"Researchers suggest that because variation in drug use susceptibility is in part due to genetic factors, drug consumption could potentially be a costly and honest signal of biological quality. The hypothesis being that humans engage in substance use despite health costs in part to evidence that they can afford to ... |
the science behind the charlie charlie pencil game | The kid off camera to the right is blowing slightly, moving the pencil. Try it yourself, it takes very little wind to move the pencil. You can tell because they never show anybody in frame when the pencil is moving.
This is really no different than the telekinesis trick James Hydrick used to make pencils move back in the eighties. | [
"The Charlie Charlie challenge is a modern incarnation of the Spanish paper-and-pencil game called \"Juego de la Lapicera\" (Pencil Game). Like a Magic 8-Ball, the game is played by teenagers using held or balanced pencils to produce answers to questions they ask. Teenage girls have played \"Juego de la Lapicera\" ... |
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